Convert Coulombs to Ah

Convert coulombs to ampere-hours by entering a value below.

1 C (coulombs) = 0.0002777778 Ah (ampere-hours)

How to Convert Coulombs to Ampere-hours

The coulomb and ampere-hour are both units of electric charge. By definition, 1 ampere-hour equals exactly 3600 coulombs. This means to convert coulombs to ampere-hours, you divide by 3600.

Formula

ampere-hours = coulombs ÷ 3600

Step-by-Step Example

Convert 5 C to ampere-hours:

1
Convert 5 C to ampere-hours

We need to convert coulombs to ampere-hours

2
Apply the formula

Since 1 Ah = 3600 C, divide by 3600

5 ÷ 3600 = 0.0013888889

Answer

5 C = 0.0013888889 Ah

Coulomb to Ampere-hour Conversion Table

Quick reference table for common coulomb to ampere-hour conversions. Click any value for detailed calculation.

Coulombs (C) Ampere-hours (Ah)
0.1 C 2.7777777778e-5 Ah
0.5 C 0.0001388889 Ah
1 C 0.0002777778 Ah
2 C 0.0005555556 Ah
5 C 0.0013888889 Ah
10 C 0.0027777778 Ah
25 C 0.0069444444 Ah
50 C 0.0138888889 Ah
100 C 0.0277777778 Ah

About These Units

Coulomb (C)

The coulomb (C) is the SI unit of electric charge, defined as the charge transferred by 1 ampere flowing for 1 second. One coulomb equals 6.242×10¹⁸ elementary charges (electrons or protons). Named after physicist Charles-Augustin de Coulomb. Formula: Q = I × t (charge = current × time).

Ampere-hour (Ah)

An ampere-hour (Ah) equals 3,600 coulombs—the charge delivered by 1 ampere flowing for 1 hour. Standard battery capacity unit: car batteries 50-100 Ah, deep-cycle batteries 100-400 Ah, EV batteries measured in kWh (Ah × voltage). One Ah = 1000 mAh.

Frequently Asked Questions

How do I convert coulombs to ampere-hours?

To convert coulombs to ampere-hours, divide the value by 3600. For example, 10 C = 0.0027777778 Ah.

How many ampere-hours are in 1 coulomb?

1 coulomb equals 0.0002777778 ampere-hours.

What is the formula for coulombs to ampere-hours?

The formula is: Ah = C ÷ 3600.