Convert

Coulomb to Ampere hour

Exact answer: 1 C = 0.000277777778 Ah (exact defined factor)

Coulomb and Ampere hour describe the same quantity from the Electric charge family but come from different systems of units. The factor is defined exactly. Charge appears with batteries, power banks, capacitors and in electrical engineering.

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What do you want to convert?

From3,600 C

Result1 Ah

Factor1 C = 0.000277777778 Ah

Source basisBIPM SI Brochure · NIST Guide to SI Appendix B

Examples

013,600 C = 1 Ah

Example value from the reference table. Internal calculation uses stored factors; display output is rounded.

02Common mistake

Ampere hours measure charge, watt hours measure energy. mAh and Wh are only linked through voltage: Wh = Ah × volts. Two batteries with identical mAh can store different amounts of energy.

03Base unit: C

1 C = 0.000277777778 Ah. Coulomb is the base unit of the family, so the value is converted directly.

Table

Coulomb to Ampere hour
Coulomb	Ampere hour
3,600	1
7,200	2
18,000	5
36,000	10
72,000	20
360,000	100

Formula

1 C = 0.000277777778 Ah. Coulomb is the base unit of the family, so the value is converted directly.

Sources

BIPM SI BrochureSI base units, prefixes and official SI context.NIST Guide to SI Appendix BNIST conversion-factor method and non-SI factors.

Related conversions

Ampere hour to Milliampere hourAh → mAhElectric charge Milliampere hour to Ampere hourmAh → AhElectric charge Ampere hour to CoulombAh → CElectric charge Milliampere hour to CoulombmAh → CElectric charge

Search and practice paths

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Factor origin

Factors come from the stored source family and are not derived from rounded display values.

Rounding rule

UnitCloud keeps calculating with stored factors and rounds only the displayed output by selected precision.

When not to use

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.

Citation

Citation note: UnitCloud, conversion with formula, sources reviewed: September 2026. Electric charge. Source basis: BIPM SI Brochure · NIST Guide to SI Appendix B.

Common questions

What is the factor for Coulomb to Ampere hour?

1 C = 0.000277777778 Ah

Which formula does Coulomb to Ampere hour use?

1 C = 0.000277777778 Ah. Coulomb is the base unit of the family, so the value is converted directly.

What is the most common mistake?

Ampere hours measure charge, watt hours measure energy. mAh and Wh are only linked through voltage: Wh = Ah × volts. Two batteries with identical mAh can store different amounts of energy.

When should I verify the result?

Do not use as the sole basis for official, medical, safety-critical or contractual decisions.