Ans

Unit converter

Electric charge.

Convert mA·h to C, or pick any of the 4 units in the menus. Type in either box and the other follows. Coulombs and the milliampere-hours printed on batteries. Turning mAh into watt-hours needs a voltage, so it is not a conversion and is not offered.

mA·h → CExact definition
—
Milliampere-hours to coulombs — common values, to 6 significant figures.
mA·hC
1 mA·h3.6 C
2 mA·h7.2 C
3 mA·h10.8 C
4 mA·h14.4 C
5 mA·h18 C
10 mA·h36 C
15 mA·h54 C
20 mA·h72 C
25 mA·h90 C
50 mA·h180 C
75 mA·h270 C
100 mA·h360 C
250 mA·h900 C
500 mA·h1800 C
1000 mA·h3600 C
1 mA·h=3.6 C 1 C=0.2777777778 mA·h

Definitions

  • The milliampere-hour is the capacity marked on phone and tool batteries. Turning mAh into watt-hours needs the cell voltage as well, so it is not a unit conversion.
  • The coulomb is the SI unit of electric charge: one ampere flowing for one second.
  • Charge is not energy. Converting mAh to Wh requires a voltage, so this converter deliberately does not pretend those are interchangeable units.
  • Every unit in the menus is exact by definition, so the only rounding on this page is the one you choose for the display.

How it works

Every value is converted into coulombs and then back out into the unit you asked for. One route covers every pairing in the menus, so an unusual combination is no less accurate than a common one, and adding a unit affects only that unit.

Both boxes are live. Whichever one you last typed in is the source, changing either menu recalculates straight away, and Swap exchanges the units and the values so the number you are reading stays where you are looking.

Display precision sets a maximum number of significant figures and trims trailing zeroes, so it changes what you see and never what was calculated. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: how many coulombs in a milliampere-hour (3.6), how many milliampere-hours in a coulomb (0.277778), and what 1000 mA·h is in coulombs (3600 C).

From the maker of Ans — a scientific calculator you can own. Same idea: a proper instrument, nothing in the way.