Cooking
Microwave Running Cost Calculator UK
Estimate the cost of heating, defrosting or cooking with a microwave.
Estimated running cost
- Per hour
- 24.67p
- Per day
- 4.11p
- Per week
- 28.77p
- Per month
- £1.23
- Per year
- £15
Formula: microwave input wattage ÷ 1,000 × minutes ÷ 60 × electricity price.
Cost table
| Scenario | Power | Use time | Cost at 24.67p/kWh |
|---|---|---|---|
| 800W for 3 minutes | 800W | 0.05 hours | 0.99p |
| 1,000W for 5 minutes | 1,000W | 0.08 hours | 2.06p |
| 1,200W for 10 minutes | 1,200W | 0.17 hours | 4.93p |
Formula
microwave input wattage ÷ 1,000 × minutes ÷ 60 × electricity price = running cost
For example, a 1,000W microwave used for 0.0833 hours at 24.67p/kWh costs 1 x 0.0833 x 24.67p = 2.06p.
Ways to reduce the cost
- Use a microwave for reheating small portions instead of a full oven.
- Cover food where suitable to reduce heating time.
- Use correct power settings to avoid repeated cycles.
- Defrost in the fridge when time allows.
FAQs
How much does a microwave cost per minute?
A 1,000W microwave costs about 0.41p per minute at 24.67p/kWh.
Is a microwave cheaper than an oven?
For reheating and small portions, usually yes.
Is input wattage different to cooking wattage?
Yes. The wall-socket input can be higher than the advertised cooking output.
Can I use minutes?
Enter decimal hours or use 0.083 for about 5 minutes.
Last reviewed 3 May 2026. Source: Ofgem energy price cap. Figures are estimates. Actual prices vary by region, supplier, tariff, payment method and meter type.