Conversion guide

Kilowatts to Kilojoules conversion

Calculate energy in kJ from average power in kW and an explicit duration in seconds. Runs locally in your browser.

Kilojoules to kilowatts Kilowatts to joules

Instant result

Result

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Enter values to convert.

Inputs —

Mode —

Formula —

Formulas

Core equations used by this converter.

EnergyE(kJ) = P(kW) × Δt(s)

Exact definition1 W = 1 J/s

iAverage power is measured over the same interval as the energy. Displayed results may be rounded.

How to use

Enter average power

Use kW for the first field.

Enter the duration

Use seconds. The duration must be nonnegative.

Read the result

The result updates in kJ.

Example conversions

Common values with formula and result.

3 kW for 3 seconds

3 × 3 = 9 kJ

9 kJ

2 kW for 60 seconds

2 × 60 = 120 kJ

120 kJ

1.5 kW for 10 minutes (600 s)

1.5 × 600 = 900 kJ

900 kJ

5 kW for 1 hour

5 × 3600 = 18 000 kJ

18 000 kJ

Kilowatts to Kilojoules conversion specification

Version 1.1.1 · Engine tested

Calculation status

Engine tested 4 published cases
Named expert review Not performed
Calculation version 1.1.1

Review policy

Definition: Multiply average power by the elapsed time to find energy. Use seconds for the duration on this page.
What it calculates: Calculate energy in kJ from average power in kW and an explicit duration in seconds. Runs locally in your browser.
Inputs: Average power (kW)
Duration (s)
Outputs: Energy (kJ)
Formula: E(kJ) = P(kW) × Δt(s)
Kilowatts to kilojoules table (per second): Power (kW) Energy in 1 s (kJ) Energy in 1 h (kJ)
0.1 kW 0.1 kJ 360 kJ
0.5 kW 0.5 kJ 1800 kJ
1 kW 1 kJ 3600 kJ
2 kW 2 kJ 7200 kJ
3 kW 3 kJ 10 800 kJ
5 kW 5 kJ 18 000 kJ
10 kW 10 kJ 36 000 kJ
Assumptions: Average power is measured over the same interval as the energy.
Runs locally with pinned UUCE unit definitions.
Units: kW
s
kJ
Boundary conditions: Empty or invalid input yields no valid result.
Average power must be nonnegative.
Duration must be nonnegative.
Example: 3 kW for 3 seconds → 9 kJ
Validation cases: 3 kW for 3 seconds → 9 kJ
2 kW for 60 seconds → 120 kJ
1.5 kW for 10 minutes (600 s) → 900 kJ
5 kW for 1 hour → 18 000 kJ
Sources: NIST SP 330, Appendix 1 (https://www.nist.gov/pml/special-publication-330/sp-330-appendix-1)
NIST SP 330, Section 4 (https://www.nist.gov/pml/special-publication-330/sp-330-section-4)
CalculatorX UUCE snapshot 0.3.0-preview.3
Calculation version: 1.1.1

Power (kW)	Energy in 1 s (kJ)	Energy in 1 h (kJ)
0.1 kW	0.1 kJ	360 kJ
0.5 kW	0.5 kJ	1800 kJ
1 kW	1 kJ	3600 kJ
2 kW	2 kJ	7200 kJ
3 kW	3 kJ	10 800 kJ
5 kW	5 kJ	18 000 kJ
10 kW	10 kJ	36 000 kJ

Background

Interpretation and common distinctions.

Enter the duration in seconds to calculate energy. Results for Kilowatts to Kilojoules conversion update locally in your browser.

Frequently asked questions

Key distinctions behind the conversion.

How do you convert using Kilowatts to Kilojoules conversion?

Multiply average power by the elapsed time to find energy. Example: 3 kW for 3 seconds → 9 kJ.

Can I switch direction?

Open a related calculator to use a different input and output pair.

Does this run online or locally?

Calculation runs locally in your browser. Values are not uploaded.

How precise are the results?

Results follow the formulas on this page. Round to the precision your use case needs.