mAh to Wh (Milliamp Hours to Watt Hours) Calculator

Easily convert milliamp-hours to watt-hours and vice versa using voltage. Ideal for battery ratings, power banks, and solar storage planning.

Formula

Watt Hours (Wh) = (mAh × Volts) ÷ 1000

mAh = (Wh × 1000) ÷ Volts

Example Calculations

• 5000 mAh at 3.7 V = 18.5 Wh
• 2000 mAh at 5 V = 10 Wh
• 10000 mAh at 12 V = 120 Wh
• 18.5 Wh at 3.7 V = 5000 mAh
• 10 Wh at 5 V = 2000 mAh

Frequently Asked Questions (FAQs)

1. Why do I need voltage to calculate watt-hours?

Watt-hours represent total energy. To find them from mAh, you must include voltage, since power = current × voltage.

2. What devices use mAh ratings?

Mobile phones, battery packs, cameras, and many small electronics use mAh to describe battery capacity.

3. Can I convert mAh to Wh without knowing voltage?

No — voltage is required. Without it, you can’t calculate the energy stored or delivered.

4. How do I go from Wh to mAh?

Multiply watt-hours by 1000, then divide by voltage. The second calculator on this page does it for you instantly.

Where This Is Used

• Power banks: To estimate how many charges a device can deliver
• Lithium-ion batteries: Common in phones, laptops, drones, and RC vehicles
• Solar battery sizing: To plan energy storage capacity based on mAh or Wh ratings

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