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Converters

Electric Charge Converter

Convert electric charge accurately between coulombs and SI-prefixed coulomb units, plus microampere-hours, milliampere-hours and ampere-hours for battery and electrical calculations.

Example: a battery is rated at 2,500 milliampere-hours. What is the equivalent charge in coulombs?
Result 9,000 C 2,500 mAh = 9,000 C
One-unit equivalent 1 mAh = 3.6 C A quick way to understand the relationship between the two units.

✓ Coulomb and ampere-hour relationships follow SI definitions and NIST-published conversion factors

How is the conversion calculated? The coulomb (C) is the SI unit of electric charge, with 1 coulomb equal to 1 ampere-second. Because 1 hour equals 3,600 seconds, 1 ampere-hour equals exactly 3,600 coulombs and 1 milliampere-hour equals 3.6 coulombs. Coulomb multiples and submultiples use exact decimal SI prefixes.

This calculation runs in your browser. Your values are not sent to our server.

Common electric-charge conversions

  • 1 millicoulomb (mC) = 0.001 coulomb (C)
  • 1 coulomb (C) = 1,000 millicoulombs (mC)
  • 1 microcoulomb (µC) = 0.000001 coulomb (C)
  • 1 milliampere-hour (mAh) = 3.6 coulombs (C)
  • 1 ampere-hour (Ah) = 3,600 coulombs (C)
  • 1,000 milliampere-hours (mAh) = 1 ampere-hour (Ah)

How it works

  1. Enter an electric-charge value, then choose the source and target units.
  2. Example: 2,500 milliampere-hours equals exactly 9,000 coulombs.
  3. The coulomb (C) is the SI unit of electric charge, and 1 C = 1 A·s.
  4. Because 1 hour is exactly 3,600 seconds, 1 Ah = 3,600 C and 1 mAh = 3.6 C.
  5. Pico, nano, micro, milli, kilo and mega coulomb units use exact SI decimal prefixes.
  6. This tool converts quantities of electric charge only; it does not estimate battery energy, runtime or state of charge.
Conversion factor sources

FAQ

How many coulombs are in 1 mAh?

1 milliampere-hour equals exactly 3.6 coulombs.

How many coulombs are in 1 Ah?

1 ampere-hour equals exactly 3,600 coulombs.

How many coulombs are in 2,500 mAh?

2,500 milliampere-hours equals exactly 9,000 coulombs.

How many mAh are in 1 coulomb?

1 coulomb is approximately 0.2777777778 milliampere-hours.

Does mAh measure battery energy?

No. mAh measures electric charge. Battery energy also depends on voltage and is commonly expressed in watt-hours.

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