The iPhone features remarkable battery life, however, not every user experiences peak performance. It is essential to calibrate the lithium-ion battery periodically. This article details the process for maintaining your iPhone’s battery, which will ensure more accurate battery metering. This method also applies to the iPad and iPod Touch, as well as most other devices with lithium-ion “smart” batteries.
Why Calibrate?
Lithium-ion batteries degrade as they age and undergo repeated charging and discharging cycles. Operating systems, such as iOS, track the battery’s operating range. Regardless of wear and age, battery tracking requires occasional adjustment. Battery calibration helps iOS re-calculate the range of battery life. One should calibrate the battery periodically (every 1 – 3 months) and after every major iOS update. If you upgrade iOS and notice diminished battery life, inaccurate battery metering or unexpected shutdowns, try calibrating the battery before anything else.
Battery University, an online authority on batteries of all types, recommends calibrating smart batteries:
The chemical battery representing the actual energy storage remains the master while the digital battery provides peripheral support by relying on the information obtained from charge and discharge cycles. But like all fine machines, precise settings begin to shift and need adjustment. The same happens with an SMBus battery that also require periodic calibration. The instructions for an Apple iPad reads: “For proper reporting of SoC, be sure to go through at least one full charge/discharge cycle per month.
It’s important not to confuse calibration with regular charging practices. Your iPhone’s battery will last longer if you charge your device often, before it gets down to 0%. Ideally, you should plug your device into a charger before it goes below 20%. These are ideals and not practical for most people. In real life, many people need a full day’s charge. With battery replacements from Apple as low as $49, it’s an easier solution than closely-managed charging. For those who love fiddling and want to keep their battery in optimal condition, please read “How To Extend iPhone Battery Lifespan”.
With every iOS update, new features are added, some of which affect battery life. Apple’s engineers often improve some aspects of battery life, while also introducing battery-intensive features, such as background updates. Allowing the battery to fully drain and recharge calibrates iOS to detect the full range of battery life. Some people are skeptical of this theory, and since few know the inner workings of iOS, it may sound superstitious. Research and experience have proven otherwise.
How To Calibrate the iPhone Battery
The first step is to drain the battery completely. This should be accomplished with normal use, but sometimes this may not be an option. After all, you don’t want to head off to work with 2% battery life left. Sometimes that 2% can last a few hours. It’s best to drain the battery when you can do without your device for several hours, perhaps before bedtime. If you still have a little charge left and it’s almost time to sleep, you can drain the battery more aggressively. To expedite battery drainage, turn on the flashlight, turn up the brightness, and play a video, preferably streaming over the Internet.
Once your device powers off due to insufficient battery charge, it’s best to leave it for some time. If possible, leave it overnight and don’t charge it until the following morning. This is not always an option, and if it’s too inconvenient, skip this step. Allowing the device to sit overnight will further drain the battery. You may notice that even when your iPhone runs out of juice and powers down, when you immediately plug it back in, you will see it at 2-3% charge. This is partly due to the fact that some battery life was remaining when it powered down. To keep your data safe, iOS has to power down before the battery is fully drained. Otherwise, it would shut off without being able to save its state to secondary storage.
Next, plug your iPhone into the charger. Keep it in the charger until it’s at least 100% charged. If possible, keep it in the charger longer. According to Apple, 100% means that you will get the expected battery life, but the device can charge beyond this.
So, here’s how things work: Apple does in fact display the iPad (and iPhone and iPod Touch) as 100 percent charged just before a device reaches a completely charged state. At that point, it will continue charging to 100 percent, then discharge a bit and charge back up to 100 percent, repeating that process until the device is unplugged.
Doing so allows devices to maintain an optimum charge, Apple VP Michael Tchao told AllThingsD today.
“That circuitry is designed so you can keep your device plugged in as long as you would like,” Tchao said. “It’s a great feature that’s always been in iOS.”
Keeping the device in the charger after it reaches 100% will ensure it is fully charged. Two additional hours should do it.
It is best to charge your iPhone when it is off. After you plug in the charger, your iPhone will automatically start up in a few minutes. When it is back online, simply hold down the sleep/wake button and slide your finger over the off switch. Your iPhone will charge faster when it is off. It will also generate less heat, which will extend overall battery life.
If you turn your iPhone off to charge, make sure to estimate how long it will take to charge beyond 100%. Three hours is a safe bet for an iPhone 11. My iPhone 6 will charge to 100% in three hours, but the extra two hours ensures that it is fully charged — beyond 100%.
Now that your device is fully charged, you should reset it. This is done by holding down the sleep/wake button (on the top of the device) and home button, until the Apple logo appears. If you have a newer iPhone, without a physical Home button, hold the volume up and sleep/wake button. Your device will boot up and is now reset. Remove the charging cable when your device is up and running.
Step By Step Battery Calibration
The following process is what I consider to be the gold standard of iPhone battery calibration. For some, it might not be possible to follow all of these steps. If you are an on-call professional or hopelessly addicted to your iPhone, you might not be able to turn off your iPhone overnight or even for a few hours. At the bare minimum, you need to drain the battery until the device shuts off, charge your iPhone to 100%, and reset it by holding down the sleep/wake and home buttons until you see the Apple logo.
1. Use your iPhone until it shuts off automatically. If it is near 0% battery life and you want to drain it faster, turn on the flashlight, turn up screen brightness all the way and play a video, preferably streaming from the Internet.
2. Let your iPhone sit overnight to drain the battery further.
3. Plug your iPhone in and wait for it to power up. Make sure to use the charger supplied by Apple or one that runs at the same wattage and amperage.
4. Hold down the sleep/wake button and swipe “slide to power off”.
5. Let your iPhone charge for at least 3 hours. Older iPhones should be charged for 5 hours. The charge progress indicator is not displayed while your iPhone is turned off.
6. With the charging cable still connected, press the sleep/wake button for about a second to start up your iPhone.
7. When the iPhone has booted up, hold down the sleep/wake and home buttons until you see the Apple logo. If you have a newer iPhone, without a physical Home button, hold the volume up and sleep/wake button.
8. When your iPhone is back online, remove the charging cable.
Addressing the Critics
Numerous critics of battery calibration have emerged. They post (often nasty) comments and there’s even a top-ranking article debunking battery calibration, specifically mentioning this Appledystopia article. Riddled with contradictions, confusion and conflation, their main argument is that completely draining a lithium-ion battery is harmful. This is partially true, but battery calibration is not done every day. Battery calibration is performed periodically, no more than once every one to three months.
Draining your iPhone’s battery isn’t that harmful. Most people do this quite often, in the process of using their iPhone throughout the day. It’s not optimal, but it will not totally destroy your battery. The benefit of calibration outweighs running your iPhone down to 0% once every few months. Your device will have a more accurate battery meter. With more accurate battery metering, there won’t be any unpleasant surprises, such as missing that important conference call because your iPhone went from 30% to 5% in 30 minutes.
On the opposite side, they argue that fully charging an iPhone also damages the battery. Apple already has technology in place to carefully manage the last 20% of the charging process. Once your battery charge progresses over 80%, the iPhone’s power IC reduces charge current. This is known as a trickle charge. Reducing the charge stresses the battery less than running at full current. This is all the more reason you need to calibrate your iPhone battery. Your iPhone relies on accurate battery metering to determine when the trickle charge starts. Calibration helps ensure that the iPhone’s smart battery is accurate.
Critics suggest that calibration, by running the battery between two extremes, will do more harm than good. Again, this is a process that’s done once every 1-3 months. Most people drain their iPhone battery from use. They charge their iPhone all the way. If you do this methodically and throw in a system reset, you’ve just calibrated your iPhone. There’s nothing mysterious or damaging about this process. Everything is done within normal operating parameters of the device. People run their battery from 0% to 100% every day, for years on end. The whole point of calibration is to have an accurate battery meter. Performing calibration periodically won’t diminish iPhone battery lifespan. In fact, you can get more life out of a failing battery with calibration. Calibration ensures that processes such as trickle charging are more precise, as they rely on accurate battery statistics. Read the comments — they’re testimonials to battery calibration.
Critics of this article don’t tell their readers to turn off their iPhones while charging. When an iPhone is on and plugged in, it generates more heat while charging, which will shorten the battery’s lifespan. Despite this fact, most people will leave their iPhone on while charging. They’ll even continue to use it, even when it’s warm to the touch. It’s easier and more convenient to do so, but it does harm the battery.
The Appledystopia battery calibration guide, however, recommends turning the iPhone off, which charges the battery with less heat than typical charging. The battery also charges faster this way, as the device is no longer consuming power. The notion that calibration harms a battery is bunk. Everything is done within normal operating procedures. iPhone users run their battery down every day. They charge their device to 100% all the time. To label this behavior damaging is delusional. Appledystopia isn’t trying to alter the way you use your iPhone every day. This article is simply outlines a procedure to calibrate the iPhone’s battery meter. I feel sorry for the poor soul who’s suckered into using 60% of their battery range, so they can make their battery last for a few more weeks. Such people can’t see the forest for the trees!
Critics of this article contradict themselves. One one hand, they suggest that Apple successfully manages all aspects of battery charging, including calibration. They silently fixed this issue, according to some. Then, in their same article or comment, they contend that draining and fully charging the battery is incredibly harmful. Which one is it? Does Apple provide users with a device that’s harmful to fully charge and discharge? Or do they manage every aspect of charging, including calibration? The answers are a bit complex, but they’re not the polarized contradictions that my critics spew forth. It’s safe to fully charge and discharge your battery, but not optimal.
Apple devices, to date, still need battery calibration. This includes the new iPhone 11 line. Apple has not silently fixed this issue. It’s true that Apple has made advances in battery management, but their website neither condones nor dismisses battery calibration. In my research, I have found iPhone users who had their device batteries calibrated at the Apple Store.
Some brands of smartphone do not need to be calibrated. Google’s Pixel line doesn’t need calibration, and they specifically mention this on their battery care page. It’s unclear how they manage diminishing battery lifespan on their device. Critics of this article claim that Apple has done the same thing, but they won’t mention it. That’s a big assumption to make. They could easily report this self-calibrating feature on their battery management page.
It makes sense for them to remain silent about calibration. Most people will just go to the Apple Store and maybe purchase something while there. It makes their product seem inferior. They have made no indication whatsoever that battery calibration is part of iOS 13 or any new release. Battery calibration requires that the user run the battery down to 0% and back to 100%, to determine the full range. Apple may do this discretely if this behavior occurs. If that’s the case, however, users can still follow this guide to initiate calibration themselves. Some may always top off their iPhone and never run the full range. When Apple admits that battery calibration is no longer necessary, I will be the first to update this guide. Until then, I’ll stick with the evidence at hand.
Critics take a cheap shot, claiming that I advocate turning on the flashlight, amplifying screen brightness and other measures to rapidly drain the battery. Yes, but only if you’re close to 0%. My critics didn’t miss that, yet their writing indicates that this is a long-running process. It’s their pathetic attempt to create a straw man. I never suggest turning every bell and whistle on and all the way up, in order to drain an iPhone from 100% to 0%. That’s an intentional deception put forth by my critics.
Battery calibration isn’t just backed up by anecdotes. Although many people have noticed significant improvement in battery meter accuracy, there’s proof beyond these accounts. Battery University provides some of the best information on lithium ion battery care. They wrote a whole article on how to calibrate a smart battery, which has been referenced by Appledystopia several times. Their guide is an excellent resource, however, it’s not specific to the iPhone.
If battery calibration works for you, or not, let Appledystopia know! Drop a comment below.
Make Your iPhone’s Battery Last Longer
A lot of people visit this site because their iPhone’s battery is shot. Calibration can help in some cases, but it is not a panacea. If calibration doesn’t improve your iPhone’s battery life, it may be time to replace the battery. Fortunately, you can prolong the lifespan of your new battery by following a few tips. For more information, please read “How To Extend iPhone Battery Lifespan”.
More Information
Many users are skeptical of this process and feel it is superstitious. I hope I have shed light on the reasons why you should calibrate your iPhone battery. If you doubt this article, take screenshots of your battery life (Settings > General > Usage) before and after conditioning the battery. I have found this process to work. Of course, your battery may drain at different rates depending on use. For more information and tips about lithium-ion batteries, please read this article.
Follow Appledystopia on Google News
Share This Page
Autumn says
Thank you so much for this article. I’m not sure if you can help me – I am running into an issue with my iPhone 8. I bought it refurbished in January and the battery life was awesome – I got it because my 5S was abruptly unable to hold a charge despite replacing the battery. A couple weeks ago in the span of two days my 8 is suddenly incapable of staying powered on unless it’s plugged in. It will say it’s fully charged and then turn off in 30 seconds and when I plug it back in it will restart and tell me the battery is anywhere from 1% to 100%! The issue is that I cannot get it to drain. I believe it’s more or less fully charged and so it would probably take days of me being unreachable by phone to discharge completely (being powered off, not plugged in with a full battery).
I wish I knew about your procedure when I used my 5S because I bet it was the same issue. In order to fix my current situation, I tried reviving the 5S so I could swap out phones while the 8 drains its battery but the 5S will not power on, so I’m guessing the battery is toast. I could replace that battery again (which was an enormous pain) and see if it will say least limp along, or attempt to use my friggin 4S if my phone company can transfer it over temporarily while I let my perfectly good 8 sit there trying to drain. Do you have any suggestions on a solution for my weird situation?
Appledystopia says
I concur. Your battery is toast. Most refurbished phones come with a warranty. If the warranty hasn’t expired, try getting the battery replaced. Apple also reduced the price on battery replacements, and there are third-party repair shops that can do it for less. Just make sure they’re certified and the parts are genuine.
Before you do this, it’s a good idea to check your iPhone’s battery health. Go to Settings > Battery > Battery Health. Apple’s warranty policy (adopted by third-parties, like Best Buy) is that they won’t replace a battery unless the health is below 80%. The battery health stat will tell you what condition your battery is in.
Sam K says
Anytime I go to the apple store to get the battery replaced on an IPhone or IPad, the apple store staff and management bluntly tell me that apple does not replace batteries. In every instance I have been asked to upgrade to a new phone or IPad .
I’ve tried apple stores in NY, NJ, FL, CA, TX.
All Apple stores give me the same story.
Even Best Buy advised me the same.
Due to this I have several unusable IPhones and IPads.
Do you have a suggestion how I can get the batteries replaced?
Appledystopia says
I tried to do this back when Apple had the $29 battery replacement deal, as an apology for slowing down iPhones with failing batteries. BestBuy wouldn’t replace my battery, as the battery health meter was not below 80%. I called Apple and, only because of that current $29 deal, they offered to replace my iPhone 6 battery. Normally, if your iPhone’s battery health is over 80% they will not replace it, as a matter of consumer protection. If it’s above 80%, the battery should give you a full day of use. They do it so that unscrupulous repair shops can’t rip off Apple customers.
You can check battery health by tapping on Settings > Battery > Battery Health. If this statistic is above 80%, Apple and affiliated repair shops won’t replace your battery, as it doesn’t need replacing.
If your Apple device has below 80% battery health and they still refuse to replace the battery, call Apple’s customer support. I did this, and I should have done it in the first place. Dealing with BestBuy was a waste of time.
Anonymous says
If you had been in India this would have resolved with very reasonable rates within hours.
Appledystopia says
Probably. I wish I could send my mom’s 27″ iMac to India to have it fixed. The Apple Store can’t seem to fix it, and it’s their own computer!
ali says
I replaced my iPhone 8 battery. It’s health is 100% but its last only 2 hours if I charged 100%. What can I do?
Appledystopia says
You should contact customer service. I think the replacement battery may be defective and, for whatever reason, its showing 100% health. Since Apple is so secretive and clandestine, no one knows how they come up with their battery health statistic. A fully charged iPhone should last 8-10 hours, depending on what you’re doing.
CHERYL A CAYER says
Hi there. Thank you for this info. I have just had a new battery installed in my iPhone SE. When it died, eventually, I found this article of yours. Is it a good idea to calibrate a new battery?
I did leave it to completely drain overnight, plugged it in this morning to boot up, and shut it off, as recommended. I am planning on leaving it off, with the charging cable connected for 5 hours.
What do you think? New batteries need calibration or no?
Thanks so much,
Cheryl
Appledystopia says
It all depends on its behavior. If it is shutting down unexpectedly, you should calibrate it. If it behaves normally, and you can still use the phone at 1%, then just do it periodically, when it’s convenient.
Opportunities for calibration present themselves. If it’s late night, my phone it at 4% or something and I haven’t calibrated it in a while, I’ll just do it then.
I switched to Android, and I calibrate my new phone as well.
Marondi says
Please my phone has been acting up late goes on and goes off itself ,,,,please help me what can i do
Nadia says
Hi There!
Thanks for this article..Im following the steps hopefully it will work like Magic for me:).
My iPhone 6S plus is gone into Panic-Full mode(Switching on and off pretty much not usable).(Its Battery health is at 69%)and I cannot update it to iOS 14.2. Currently on iOS 13.6.
1.Do you think calibrating the battery will help me update it successfully?
2.Or DO you think that Replacing my Battery will help from panic-Full log to successfully downloading and installing the new iOs 14.2??
3. Apple Store said my phone is of no use now and will need to get a new one.:(
Any help is much appreciate 🙂
Many Thanks.
Appledystopia says
Of course the Apple Store wants you to get a new one. Apart from OnePlus, every other smartphone maker has lost year-over-year sales in 2020. Apple is desperate to sell new iPhones. The iPhone 6S is still a viable phone, however. You can run iOS 14 on a 6S. I would recommend replacing the battery if the price is reasonable. It’s only $49 for an iPhone 6S. With 69% battery health, it’s completely normal for it to shut down randomly. When it goes under 80%, all bets are off…
I had the battery on my iPhone 6 replaced about two years ago, when Apple offered the $29 battery replacements as an apology for slowing down devices without user knowledge or consent. Although I switched to Android, I still use this iPhone 6 as a music player. It was a great decision. Currently, this iPhone has 97% battery health. Not bad!
You can try calibrating the battery. It might stop the unexpected shutdowns. Replacing the battery definitely will…
I have been reading of many complaints about iOS 14 draining battery life. Customers believe Apple is doing this on purpose to drive sales of iPhones. I don’t know if this is true, but it’s something to watch.
Nadia says
Thank you that was my next move to replace the batteries :). Thanks again for your prompt reply! 🙂
Abel Johnson says
Please sir how do I get my phone’s battery life back to 100%?
I bought this phone barely two months now and it has 99% battery health now.
It’s an iPhone 11promax
Appledystopia says
Unfortunately, the only way to get Battery Health back to 100% is to replace the battery. Apple won’t do that until it goes below 80%.
99% seems about normal for two months of use, depending on how you use it. Don’t worry about it. Use it until the battery doesn’t perform well, and either replace the battery or phone.
lawrence says
I replaced the battery of my iPhone 6 from a third party service center. It shows a 100% battery health but the battery drains fast and no stand by time whatsoever.
Can this recalibration help fix this issue or doing a factory reset will?
Appledystopia says
I recommend trying the calibration process on your iPhone. Your iPhone is probably still setup to use the old battery, which is why the metering is so far off.
Gernot says
Hi there,
My 2-year-old iPhone SE all of a sudden started to show annoying behaviour: after charging, battery health drops from 100% to 20% in about half an hour.
Then, after dismissing dialog that recommends going to “Power save mode” a couple of times, it quickly drains to single-digit percentages.
However, I’m still capable of using it for hours, even with 1% charge level displayed. Thus, the battery life is not actually reduced – only the computed charge level is completely off.
I have already followed advice such as yours at least thrice, attempting a “re-calibration” – it hasn’t worked at all 🙁
However, I have always skipped step 7 (i.e. reset the iPhone immediately after fully charging it).
Could that actually make the difference?
Appledystopia says
Yes, the reset at the end clears out cached data. Apple doesn’t provide any information as to how these features work, but it is known that soft resets delete cached data. Try the process again, but do the soft reset at the end. Please let us know how it works out! Thanks!
Gernot says
I followed your instructions very thorouhly, but, unfortunately, it did made not difference…
So I’ll probably keep using the phone the way it is – even though it is annoying not to know when it will finally shut off after 12 hours of “1%” charge level…
Thanks anyway!
P.S. Even though there are many instructions like yours out there, I was not able to find a comment anywhere saying that it actually worked. Maybe “battery calibration” is a kind of Urban Legend?
Appledystopia says
That’s strange that it stays at 1% for 12 hours. You may need to reset your phone. I’ve never encountered such a strange anomaly.
The comments on this page are paginated. I show the first 50, but there are hundreds. Lots of people say it works. Also, there are links to Battery University about calibrating Apple devices. They’re a very reliable source. Battery University is run by Cadex Electronics, a company specializing in lithium-ion battery technology.
Denisse says
I started this process last night on my iPhone SE 1st gen by letting video play with the flashlight on before going to bed but when I plugged the phone in this morning the apple logo came on immediately and the phone was at 5%. I left the phone at 34% before going to bed and didn’t plug it back in until 9+ hours after I had left it. Is this a true recalibration then if the phone was able to power back on so quickly?
Appledystopia says
It seems as though your phone shut down unexpectedly, when the battery was above zero. This can happen if the battery isn’t in peak condition. Indeed, such inaccurate battery metering is the problem that calibration solves.
The calibration will likely work, because it should now calibrate 0% with the same state as when the iPhone powers down.
Angel banawa says
Please sir how do I get my phone’s battery life back to 100%? Because my battery life is 62% please help me! Is it still working or will I buy a new battery?
Appledystopia says
Do you mean battery life or battery health? I’m assuming the latter — battery health. The only way you can restore battery health back to 100% is to replace the battery. Apple offers the service for a reasonable price.
Aleena Pirbhoy says
I got an iPhone 7 plus a year ago and its battery health is 83%. I updated the phone to iOS 14 2 months ago and now it stops 22% and closes down and then opens again and shows ten percent and then closes again. When I connect it to the charger it jumps to 22 percent again. How can I fix this?
Appledystopia says
Try calibrating the battery using the instructions provided. iOS 14 is particularly hard on batteries after installation. All major iOS updates run a post-installation optimization process. This usually drains the battery rapidly, even when you’re not using the phone. Often, the stress of downloading, installing and optimizing a major iOS update, while using your device normally, can stress the battery and reduce its health.
Paul.S says
18 months ago I replaced the battery in my first generation iPhone SE.
Ever since then I have used your calibration procedure every 3 months or so.
Battery performance is still almost like new and the iPhone is indicating a maximum capacity of 96%.
Appledystopia says
Glad to hear that it works. That was my experience as well. Thank you for your feedback!
miguel says
Hello there. I just wanna ask if battery calibration will help solve this problem of mine. My battery percentage increases gradually even of it is not plugged in to charge. Sometimes it’s 34% then all of a sudden after a minute it shows 38%. Will this process of yours help?? Thank you so much.
Appledystopia says
I believe calibration will likely solve this issue. It’s also possible that the battery is in poor condition. What’s your battery health like? You can check this out by tapping on Settings > Battery > Battery Health. If it’s below 80%, I recommend either replacing the battery or accepting that it won’t perform as expected. You can actually get by for some time, perhaps years, on an “unhealthy” battery.
Sheheryar Khan Wazir says
Drain your battery until your iPhone or iPad turns off, try turning it on and stop when it’s battery is 0% (So that it won’t turn ON any more). Then charge it again, that solved my issue of restart loop. Moreover after draining your battery, charge it with new charger and cable. Don’t use the old one.
Alex says
Thanks so much for this guide! Very useful! I have an iPhone 5 here that won’t charge beyond 93%. I drained the battery as per the guide, then left it charging for over 12 hours while switched off. I switched it on and the battery level showed 93%. After another hour of charging it was still on 93!
Any tips? Or shall I just do the reset as suggested and assume the battery is full?
Thanks for your help!
Appledystopia says
What does your battery health look like? (Settings > Battery > Battery Health)
Linos says
Hello and thank you for your guide.
Even though most of them were known to me since Nokia era ,it is a good thing to see all info gathered and well written on a page and to confirm that some new technology batteries need calibration too.So ,again, thank you.
My device is an iPhone 5s, 16 GB(used)/iOS:12.5.1 to 12.5.2/Kernel 18.7.0.Seller stated only 186 battery power cycles I don’t remember exactly(now as I write this -> 192).
My parcel arrived one week ago and I am testing it this whole week and of course battery was doing its thing ,thus I came up with your site.
I will get into many details and screenshots some time in the future and post them here.This is because I am trying to somehow stabilize battery efficiency-readings-rates-health(they change like the pacific climate for fuck’s sake) and to get to know this phone because it is my first time dealing with an iPhone ( and with its shitty system restrictions and of course I jailbroke it on day 2 ).
But preliminary results are positive, battery seems to “behave” and the charge holds better now( health was 68% to 70-75-78% now I get 79-82% to 85%(with fluctuations but my goal is to not drop under 80%) .
Although I did not do a hard calibration but have done 2 medium calibrations,plus one soft plus one or two fuzzy ( Hard calibration: totally empty ,like you mention, charge not even in the reservoir .Medium calibration: Drain until off ,then while phone powered off, charge all night.Soft calibration: While phone is powered on charge to 100% .Fuzzy calibration: Whatever the percentage charge until whatever the percentage load when phone powered on ).
So, to me, it seems and “feels” that it works.Like I said, I will return with more
information when possible.
All of you, writer and commenters have a good day …or night!
Appledystopia says
Thanks for your remarkable comment!
Joe says
Please my battery health is 96 but it’s on service so I want to know if calibration would help.And also does calibration of battery erase all data on your phone
Appledystopia says
If your battery health is 96%, you shouldn’t have it replaced. In fact, unless they’re running a special program, Apple won’t replace an iPhone’s battery unless battery health is below 80%. (This is true, it happened to me!)
Calibration won’t erase all data. The reset isn’t done from the settings menu. It’s a soft reset, so your apps, contacts and other data will remain after the calibration process.
OWOLABI OLAYINKA ISRAEL says
Please if my iPhone battery health degraded from 94% battery health to 76%
And this message is was shown on my battery health page
“ Your battery’s health is significantly degraded. An Apple Authorized Service Provider can replace the battery to restore full performance and capacity. More about service options…”
Can Calibration work and restore it back to it’s normal state??
Appledystopia says
It may help and it’s worth a shot. Normally, when an iPhone battery dips below 80% battery health, you will no longer benefit from full battery life. Your best bet is to replace it. Calibrating the battery helps when an iPhone’s battery is “healthy”, but the software doesn’t have the correct data to track it. Running down the battery until it shuts off, charging it fully and doing all of the other steps updates this data.
Lithium-ion batteries degrade over time. Calibration resets the data so your iPhone won’t shut down unexpectedly at 17% (or whatever). In some cases, it prolongs operating time per charge. Calibration isn’t a panacea, but it does work for many.