5W vs 10W vs 12W Charger for iPhone

Discussion in 'iPhone Accessories' started by Jades, Nov 26, 2012.

  1. Jades macrumors 6502

    Oct 15, 2012
    I've seen tons of posts here about what is the difference between the 5-watt, 10-watt, and 12-watt chargers for the iPhone and I've done an experiment myself with two iPhone 5s.

    Many claim that the 10 or 12-watt charger gets their phones charged much quicker than the standard 5-watt charger

    My conclusion - it's all in your head

    Over this weekend, I took two iPhone 5's and and plugged one into a 12W charger and another into a 5W charger. Both were at 60% battery level.

    Both iPhones reached 90% at almost exactly the same time!! Oddly, the 5W charger reached 90% about one minute before the 12W charger did.

    I performed the experiment one more time using a 5W and a 10W charger. Exact same result.

    So, at the end of the day, this idea that the iPad charger will charge your iPhone quicker is all in your head. And if you can prove that the iPad charger will charge your iPhone quicker, I would also want you to make sure that your iPhone charger isn't a fake charger or a charger not made by Apple.

    I hope this answers a lot of debates that take place in this forum in regards to charging times.
  2. ChrisMan287 macrumors 6502


    Nov 18, 2012
  3. ECUpirate44 macrumors 603


    Mar 22, 2010
    It makes sense. The iPhone dictates the power draw, 5W.
  4. Jades thread starter macrumors 6502

    Oct 15, 2012
    It might charge faster with both the 5W and the 12W - simply because the battery is 0.1 volts smaller, but I doubt that the 12W will charge faster than the 5W, unless you can prove otherwise.

    Exactly. Many people on the forum say that they like the 10/12W because "it charges so much faster". I thought the exact same thing myself. At the end of the day it's all in our heads.
  5. phr0ze macrumors 6502a

    Jun 14, 2012
    Columbia, MD
    Try the same test while both phones are running angry birds. :D
  6. Jades thread starter macrumors 6502

    Oct 15, 2012
    This weekend when I am bored I'll give it a shot and post the results :)
  7. takeshi74 macrumors 601

    Feb 9, 2011
    Nothing odd about it. The phone is the bottleneck.
  8. TCU macrumors newbie

    Dec 10, 2008
    From an electrical standpoint, if the 5W charger is able to provide the max current the Iphone draws (which I assume it does?), then it shouldn't make a difference what size charger you have. Even if you use a 100W charger it shouldn't charge any faster. That is because, unlike voltage, current is drawn by the device. Thus the Iphone only takes what it needs. Regardless weather the charger is able to provide more or not.

    Think of yourself at lunch time :D lets assume you are hungry for two slices of pizza. You will eat that much if you had two slices, or if you had 100. Only as much as you need.... although in my case I probably couldn't resist for more :D
  9. icemanzzz macrumors member

    Sep 27, 2010
    I use my iPad charger to charge my iPhone and it doesn't charge faster than the iPhone charger..
  10. Shadowbech macrumors 601

    Oct 18, 2011
    Planet iPhone
    You can also refer by watching this:


    InsanelyGreatMac did a review on the 12 W charger and he tested using the ipad 3, and the iphone 5. It showed that regardless if you use the 10 W or the 12 W to charge your phone, iPhone will only draw 5 W at maximum.
  11. Koebot macrumors member

    Oct 9, 2012
    Many people don't know the difference between wattage and amperage.
  12. JonBoy470 macrumors newbie

    Jun 29, 2004
    This video was painful to watch.

    This video was painful to watch. Using a Kill-A-Watt to measure power delivered to the device?! Really?! You're doing it wrong. First off, repeat the test with an iPhone 4S. Then, the right way to measure power delivered to the device would be to do man in the middle, which would require you to butcher a cable to hook up a couple of multimeters to measure voltage and amperage delivered to the device. The Kill-A-Watt is indicating total power drawn by the charger, which includes power the charger is dissipating internally as waste heat. You'd also want to perform this test with devices whose batteries at or very near full discharge. This is when the charging circuit will be applying maximum (and constant) charging current to the battery.

    Also remember that the device draws power to power itself before it allocates power to charge the battery. The battery gets whatever power is "left over". For a true test of charging speed, charge the phone while it is performing a CPU intensive task that also keeps the screen lit up (the previous suggestion to play Angry Birds would be effective. Something with 3D graphics like Minecraft would be even better.) the iPad charger will have greater "headroom" to charge the battery at a high rate under this scenario, whereas charging will slow to a crawl with the iPhone charger.
  13. hakr100 macrumors 6502a

    Mar 1, 2011
    East Coast
    What? Are you saying the 1000 megajoule generator/charger I bought on eBay won't charge my iPhone any faster than the apple charger? What about my MBA? Will it charge that faster?

    The price was right on the generator/charger, but the UPS delivery charges from Afghanistan were fierce! :D
  14. debudebu macrumors regular

    Dec 13, 2008

    I lost my charger and am currently traveling within SE Asia. I bought a replacement 12 watt for my phone and ipad, and last night plugged my 4s into it and the wall of the hotel. Instantly, it blew a fuse and the power in my room went out. There isn't an official Apple store in the country I'm in so there's no way to know if its legit other than it looks it. I have pretty rudimentary knowledge of electrical flows, what do you think caused this? 12 watt with 4s, crappy outlet, fake charger? I'm hesitant to plug my ipad in and test it on another outlet for fear of toasting it.

    I won't be back in the states for months and I definitely need my idevices to keep in touch. Please discuss
  15. RF9 macrumors regular

    Jul 8, 2008
    A while back I was trying to figure out why my phone charged faster in the car than at my desk and in the process proved basically what everyone is saying here.

    The iPhone will not charge faster with a 10w or 12w charger than with a 5w charger. The iPhone dictates how much current it will pull and pulls up to a maximum of 1 amp (5 watts) regardless of the charger capacity.

    I generally only buy 2+ amp chargers and carry them around becauses they work for both iPhones and iPads alike, but it won't charge the phone faster.

    Cables play a big role. Cheap cables, especially long ones often use thin wire gauge that limits the power. I have cheap 6ft cables that will only allow .6 Amps, and a 10ft which constricts down to .35 amps. Pay for reputable cables or at least ones that claim Apple certified and you're pretty much guaranteed they will carry a full 12w load to an iPad.

    Also iPads and iPhones rapid charge to 80%. Between 80% and 100% they gradually decrease current draw to reduce the charge speed (for battery health.)

    I did significant testing with a USB power meter and an Ammeter with over 18 different chargers and 20 different cables, all with the same result.
    Also if the charger doesn't claim apple compatible, then it may be limited to .5 amps.

    The Anker 40W 5 port charger (about $25) is awesome and delivers max power to all devices, (and that's with measured testing.)
  16. Fredvs79 macrumors newbie

    Feb 24, 2012
    I read that the iPhone 6 and/or 6 plus charges faster with a 12w charge adapter. Can anyone confirm that?

    Can anyone do a thorough test with charge times for a 6 or 6 plus using a 5w, 10w, and 12w charger?
  17. C DM macrumors Sandy Bridge

    Oct 17, 2011
    Yes they can take at least some advantage with more powerful chargers: http://www.macrumors.com/2014/09/22/iphone-6-and-6-plus-charging/
  18. Bamff macrumors regular

    May 6, 2013
  19. Meltdownblitz macrumors 65816

    Jan 21, 2010
    The iphone 6/ plus do charge at a faster rate because they are capable at charging at 2.1 amp vs previous iPhones at 1 amp as that article above explains. What it all comes down to is what the maximum voltage the device will take, if your charger is 10 amps your device won't charge super faster because the charger is 10 amps, there's a max limit on the device of how much power it will take to charge it. Easiest way to manage this situation is to purchase a Wall charger with a chip that determines how much amp each device needs, a popular one and by far my favorite is Anker (found on Amazon), I'm a big anker fan and I trust their products and no I do not work for them nor am I associated with them. But purchasing a wall or car charger with a chip lets you plug it in and forget how many amps you need for each device, plug it in any usb slot and let the charger do the work.
  20. C DM macrumors Sandy Bridge

    Oct 17, 2011
    The phone itself will determine how much power it can draw and draw what it can from the charger.
  21. Brian Y macrumors 68040

    Oct 21, 2012
    There will be very little difference between the 10 and 12w chargers. The 5w will be noticeably slower on the 6/+, similar to how it's slower on an iPad.
  22. enzo thecat macrumors 6502

    enzo thecat

    Apr 7, 2010
    Midwest USA
    Our (Duracell Model No. DU6117) car charger charges our phones much quicker than an apple wall charger. But the phones also get very warm, in doing so. So I'm not really sure about the validity of what you and others are saying about the phone always determining the power draw.
  23. jeremiah239 macrumors 6502a


    Nov 1, 2007
    239 Area, FL
    Sounds like your phone is drawing more power off the car charger because the car charger is 2.1a and has 2 ports so it's probably around 10w. The phone definitely does determine the power draw, that's not something that's been made up, that's how it works...
  24. C DM macrumors Sandy Bridge

    Oct 17, 2011
    Feel free to read the recently linked article a few posts back as well as many other information sources online to confirm what I and others have mentioned.
  25. RF9, Dec 24, 2014
    Last edited: Dec 24, 2014

    RF9 macrumors regular

    Jul 8, 2008
    I used to think this was going on too until I realized it was the cable I was using in the car vs home. At home I had a 6 foot cable and in the car a 3 foot. The 3ft was able to deliver a full 1 amp, but the 6 was limited to 2/3 of n amp due to it being low gauge wire. It was a cheap cable (about $1 when I bought 20 in bulk.)
    As a result I was able to quick charge in the car but at home I never reached quick charge.

    The phone limits to 1 amp draw. There is nothing special about it. No matter if you use a 10watt, 12watt, or 40watt, the phone is always going to self limit to 1 amp

    Also note that a phone will only draw 1 amp and quick charge when the battery is below 80%. Above 80% there is a drop off to about .8 amps and reduces almost linear to 100% (about .4 at 90%)

    I've done way way way too much testing with over 21 USB adapter/chargers and about 16 different brands/types of cables. Assuming the charger is iphone/iPad compatible it will always get identical performance on any iPhone. Depending on if you have a good or cheap cable, it could reduce that limit of current draw.
    Stick with apple certified cables. if you're paying less than about $11 (depending on length) for a lightning cable, it's it's highly unlikely it's certified or decent quality.

    All of my testing and investigation began because I found an inconsistency in charge performance and wanted to test it with real meters.

    I have switched to using almost exclusively the Anker 40W 5-port charger http://www.ianker.com/support-c7-g345.html (they have a new 60W 6-port). For cables I'm using Monoprice or AmazonBasics.
    For the car I'm using a TechNGo (sold at Walgreens) 2-port charger which delivers at least 3.2 amps. It charges two iPhones (1 amp each) at max rate. Their cables are also fine, but not too cheap. Still they are OK to get in a pinch. I've tested a bunch of car chargers and they all work well since little electronics is necessary because it's already DC current unlike a wall charger. So pretty much all, even 2 port, will deliver at least 1 amp per port unless they say otherwise.

    Anyway, people will believe what they want but I'm 100% sure based on my extensive testing that an iPhone will never pull more than 1 amp for charging and all chargers that perform at 5 watts or more and a decent cable all perform identically.

    Now when it comes to iPad, it's a different story. You're best off with a good high watt charger and you definitely need an Apple or certified cable to get over 2 amps (12 watts.) That's one reason I just use the Anker. It's versatile, 5 ports, and feeds anything as much as it needs.
    An Apple 12W is $20 and I got several Ankers for $25 on sale, and they're 5 port. So I went with the value there.

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31 November 26, 2012