watt-hours to kWh

1 watt-hour = 0.001 kWh, and 1 kWh = 1,000 watt-hours. The conversion is a single fixed factor: multiply Wh by 0.001. Worked: 100 Wh = 0.1 kWh; 1,000 Wh = 1 kWh.

Every battery on Earth is rated in watt-hours somewhere in its documentation — a phone at 15 Wh, a laptop at 60 Wh, an electric car at 60,000 Wh — and the kilowatt-hour, the unit the world buys electricity in, is simply 1,000 of them. The conversion is pure decimal arithmetic: divide watt-hours by 1,000 and you have kWh, with no constant, no approximation, and no room for error beyond misplaced zeros.

By EnginStack Editorial Team | Reviewed against NIST, BIPM and primary-source documentation About →
watt-hours
60 kWh
60,000 watt-hours = 60 kWh 60,000 kWh = 60,000,000 watt-hours

Authority: NIST SP 811 (SI usage guide) and the 1959 International Yard and Pound Agreement. The coefficient above is a defined value — it does not come from measurement and carries no uncertainty.

watt-hours to kWh

The watt-hour and the kilowatt-hour are the same unit at different decimal magnitudes — 1 kWh = 1,000 Wh by definition, exactly as 1 kW = 1,000 W. What makes this page worth a converter rather than a mental rule is the scale of modern batteries: an electric vehicle's 60,000 Wh pack is 60 kWh, a power station's 512 Wh is 0.512 kWh, and a home battery at 13,500 Wh is 13.5 kWh. Misplacing one zero when converting between them is a factor-of-ten error in a device's stated capacity.

kWh = watt-hours ÷ 1,000
1 watt-hour = 0.001 kWh — exact decimal definition
The factor is definitional: the kilo- prefix is exactly 1,000.

Worked Examples

Example 1: Convert a smartphone battery

15 × 0.001 = 0.015 kWh

Example 2: Convert a portable power station

512 × 0.001 = 0.512 kWh

Example 3: Convert an electric-vehicle pack

60,000 × 0.001 = 60 kWh

Common watt-hours to kWh Conversions

watt-hourskWhContext
15 Wh0.015 kWhA smartphone battery.
60 Wh0.06 kWhA laptop battery.
512 Wh0.512 kWhA portable power station.
13,500 Wh13.5 kWhA home backup battery.
60,000 Wh60 kWhAn electric vehicle's pack.

Engineering Context

The kWh to watt-hours page runs this factor backward. In the energy hub, watts to kW is the power-side counterpart — watt-hours are watts × hours, so the power converters feed directly into this page's inputs. EV battery comparisons also touch the speed and torque families when range and output are involved.

Consumer hardware is labeled in watt-hours and utility bills arrive in kilowatt-hours, so this division by a thousand is the step that makes a battery comparable with a bill. A 60 kWh electric-vehicle pack holds 60,000 Wh, and an average US household consumes roughly 30 kWh in a day, so a full vehicle pack is about two days of a house. Note that the pack figure is nameplate: manufacturers reserve a top and bottom buffer to protect the cells, and usable capacity is typically 90 to 95 percent, which is part of the gap between a range calculated from the pack size and the range the car actually delivers.

More: kWh to Wh · W to kW · J to kWh · Energy & Power Guide · Energy Hub

Related Unit Converters

kWh to watt-hours Watts to Kilowatts Joules to kWh Energy & Power Conversion Guide Energy & Power Converters

Frequently Asked Questions

How many watt-hours are in a kWh?

Exactly 1,000. The kilo- prefix means 1,000 by definition, so 1 kWh = 1,000 Wh — the same relationship as kilowatt to watt or kilogram to gram.

Why are EV batteries rated in kWh but phone batteries in mAh?

EV batteries quote energy capacity in kWh (power × time). Phone batteries historically quote charge in mAh (current × time) because the voltage is fixed, so mAh is proportional to energy. To compare across devices, convert mAh × V ÷ 1,000 to get Wh.

How much does 1 kWh cost on my bill?

Typically $0.10–0.30 depending on region and time of day. That makes a 60 kWh EV battery worth roughly $6–18 of electricity — useful for estimating charging cost from the kWh number.