Expert Verified Battery Energy Updated 2026

mAh to Joules Calculator

Convert battery capacity from milliamp-hours to energy in joules. Instantly calculate stored electrical energy based on battery capacity and operating voltage.

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5000 mAh 3.7 V MAH TO JOULES CALCULATOR
Formula: J = Wh × 3600
Input: Cap. & Voltage
Output: Joules (J)
Accurate Conversion

mAh to Joules Calculator

mAh

How to Use mAh to Joules Calculator

Calculating battery energy in joules is straightforward. Follow these simple steps:

  • 1
    1. Enter battery capacity: Enter your battery's capacity rating in mAh (e.g., 5000).
  • 2
    2. Select battery voltage: Choose the appropriate operating voltage from the dropdown list.
  • 3
    3. Enter custom voltage: If your battery's voltage is not listed, select "Custom Voltage" and enter the specific value.
  • 4
    4. Press Calculate: Click the calculate button to process the formula.
  • 5
    5. View energy: Read the energy output in both joules (J) and watt-hours (Wh).

How to Calculate mAh to Joules

To calculate energy in joules, you first determine the watt-hours and then convert watt-hours to joules. You can use these standard formulas:

Formula 1

Wh = (mAh × Voltage) ÷ 1000

Formula 2

Joules = Wh × 3600

Combined Formula

You can also use this simplified combined formula:

Joules = mAh × Voltage × 3.6

Real-world Example

Given:

  • Battery Capacity = 5000 mAh
  • Voltage = 3.7 V

Step 1

Wh = (5000 × 3.7) ÷ 1000

Wh = 18.5 Wh

Step 2

Joules = 18.5 × 3600

Joules = 66,600 J

Final Answer

A 5000 mAh battery operating at 3.7 V stores approximately 66,600 joules of energy.

mAh to Joules Chart

Values are based on a nominal battery voltage of 3.7 V. Actual energy varies depending on battery voltage.

Capacity (mAh) Voltage (V) Energy (Joules)
1000 mAh 3.7 V 13,320 J
2000 mAh 3.7 V 26,640 J
3000 mAh 3.7 V 39,960 J
4000 mAh 3.7 V 53,280 J
5000 mAh 3.7 V 66,600 J
6000 mAh 3.7 V 79,920 J
7000 mAh 3.7 V 93,240 J
8000 mAh 3.7 V 106,560 J
9000 mAh 3.7 V 119,880 J
10000 mAh 3.7 V 133,200 J

Note: Values are based on a nominal battery voltage of 3.7 V. Actual energy varies depending on battery voltage.

mAh to Joules Calculator Frequently Asked Questions

To convert milliampere-hours (mAh) to Joules, multiply the mAh value by the battery's voltage to get milliwatt-hours. Convert that into watt-hours, and multiply by 3600. The standard formula Joules = (mAh × Voltage × 3.6) yields the total energy.

While mAh measures electric charge capacity, Joules measure the total electrical energy stored. To accurately connect them, you must include the battery's voltage. Without voltage, you cannot convert a specific mAh charge rating into absolute Joules.

A typical 3.7-volt lithium-ion battery with a 3000mAh capacity contains precisely 39,960 Joules of energy. You find this by multiplying 3000 by 3.7 to get 11,100 milliwatt-hours, converting to 11.1 watt-hours, and then multiplying by 3600 seconds.

Converting milliampere-hours to Joules establishes a universally recognized measurement of absolute energy. Joules allow professionals to accurately compare the total energy contents of completely different power systems regardless of varying voltages.

Yes, one Joule is exactly mathematically equal to one watt-second. When measuring electrical energy, one single watt of power sustained for one entire second expends one Joule. This direct equivalence makes converting mAh into standard energy easier.

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