# Are all USB chargers compatible? **URL:** \ **Category:** Factual Questions\ **Created:** [December 14, 2015, 11:31pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466 "2015-12-14T23:31:18Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [December 14, 2015, 11:31pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/1 "2015-12-14T23:31:18Z")
Leaving aside the difference between USB, mini-USB, and micro-USB, can all such chargers be used interchangeably. Specifically, I have a charger that plugs into the wall and terminates in a mini-USB plug. Is it safe to use in any gadget that has a matching socket? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 14, 2015, 11:32pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/2 "2015-12-14T23:32:44Z")
Generally, yes. Although, it may not charge “big” devices like an iPad very fast. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [December 14, 2015, 11:32pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/3 "2015-12-14T23:32:58Z")
Some have more output than others. A low output charger may charge some devices very slowly or not at all. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 14, 2015, 11:48pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/4 "2015-12-14T23:48:12Z")
Note that not all things that claim to be USB actually follow all of the standards. My last phone had what was to all appearances a USB charger, but would throw up an error message if you tried to charge it with anything but the same-branded proprietary charger. No damage; it just refused to accept it. ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [December 14, 2015, 11:57pm UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/5 "2015-12-14T23:57:12Z")
No. My computer USB output won’t charge my Kindle Fire, but works fine with my phone. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [December 15, 2015, 12:01am UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/6 "2015-12-15T00:01:28Z")
> [@Boyo\_Jim](#): > > No. My computer USB output won’t charge my Kindle Fire… It should, just not as fast as with a regular charger. The Kindle may complain that it’s connected to a low power charger, but it should eventually charge. ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [December 15, 2015, 12:02am UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/7 "2015-12-15T00:02:58Z")
[We sorta just did this.](http://boards.straightdope.com/sdmb/showthread.php?t=777553) ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [December 15, 2015, 12:08am UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/8 "2015-12-15T00:08:40Z")
> [@scr4](#): > > It should, just not as fast as with a regular charger. The Kindle may complain that it’s connected to a low power charger, but it should eventually charge. Maybe, but the little charger icon on the Kindle doesn’t react. Come to think of it, it’s the same with my iPod, an old 5th gen one with a hard drive rather than flash memory. If it’s charging, it doesn’t show. Someone told me in another thread that some newer USB ports have lower power outputs than the earlier ones. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [December 15, 2015, 1:06am UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/9 "2015-12-15T01:06:44Z")
> [@Boyo\_Jim](#): > > Maybe, but the little charger icon on the Kindle doesn’t react. Come to think of it, it’s the same with my iPod, an old 5th gen one with a hard drive rather than flash memory. If it’s charging, it doesn’t show. > > Someone told me in another thread that some newer USB ports have lower power outputs than the earlier ones. the USB 1.x/2.0 standard only says that ports are required to support up to 500 mA of current. tablets might need 2-4x that to charge the piles of battery they contain. though my iPad will say “Not Charging” when connected to a PC, it will in fact charge very slowly so long as the screen remains off. USB 3.0 can supply up to 900 mA, and the newer revisions with the Type C connector increase that further. ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [December 15, 2015, 5:09am UTC](https://boards.straightdope.com/t/are-all-usb-chargers-compatible/740466/10 "2015-12-15T05:09:24Z")
> [@Richard\_Pearse](#): > > Some have more output than others. A low output charger may charge some devices very slowly or not at all. What is considered “low output”? Which value is relevant? Define “slowly” on a relative scale. Mine say 5v and 1.5 or 2.0A. Takes a couple hours to charge a tablet.