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Convert Calc

Watt-Hours (Wh) to Kilowatt-Hours (kWh) Converter

Enter a value to instantly convert between energy units.

Precision4 dp

1 Watt-Hour = 0.001 Kilowatt-Hour

Key Formulas

Kilocalorie → Kilojoule

kJ = kcal × 4.184

Kilojoule → Kilocalorie

kcal = kJ × 0.239006

Kilowatt-Hour → Joule

J = kWh × 3600000

Joule → Kilowatt-Hour

kWh = J × 2.77778e-7

Formula

kWh = Wh ÷ 1000

Both are electrical energy units; the difference is scale. Watt-hours describe portable electronics (batteries, phones, power banks), while kilowatt-hours measure household or utility electricity (your monthly bill). You convert from Wh to kWh when comparing a portable device's energy capacity to household consumption — a laptop battery (100 Wh = 0.1 kWh) might provide 10% of a home's daily electricity use, putting device energy in household perspective.

Source: NIST SP 811, Table B.8

Frequently Asked Questions

Real-World Examples

A smartphone user checking battery capacity. 15 Wh (0.015 kWh) — if electricity costs $0.15/kWh, a full charge costs about $0.0023 (less than 1 cent).

15 Wh = 0.015 kWh

A power bank spec. 1000 Wh (1 kWh) capacity, marketed as 'a full day of home electricity' — though real homes use 20–50 kWh/day, making this a meaningful portable backup.

1000 Wh = 1 kWh

A portable generator specs. 50 Wh of solar charging (0.05 kWh/day under peak sun) helps a camper understand: after 20 sunny days, it replaces 1 kWh, or runs a 5W LED lamp continuously.

50 Wh = 0.05 kWh

A backup power bank for emergencies. 400 Wh (0.4 kWh) can charge a laptop once or run a WiFi router for ~20 hours without grid power, quantified for disaster preparedness planning.

400 Wh = 0.4 kWh