How to calculate electricity cost
kWh = watts × hours ÷ 1,000, then cost = kWh × price per kWh. A 1,500 W heater running 4 hours uses 6 kWh a day. At 18¢ per kWh that is $1.08 a day, or about $32 a month.
Electricity prices in 2026
| Where | Typical price | Source |
|---|---|---|
| UK (England, Scotland, Wales) | 26.32p per kWh + 54.83p/day standing charge | Ofgem price cap, 1 Oct – 31 Dec 2026, Direct Debit average |
| United States | About 18¢ per kWh (from ~13¢ to over 40¢ by state) | EIA residential average, mid-2026 |
| Everywhere else | Check your latest bill | Look for “unit rate” or “energy charge” |
What common appliances cost to run
| Appliance | Watts | Use | UK (26.32p) | US (18¢) |
|---|---|---|---|---|
| Space heater | 1,500 | 4 h/day | £1.58/day | $1.08/day |
| Electric blanket | 100 | 8 h/night | 21p/night | 14¢/night |
| LED Christmas lights | 30 | 6 h/day | 5p/day | 3¢/day |
| Incandescent Christmas lights | 200 | 6 h/day | 32p/day | 22¢/day |
| Air fryer | 1,500 | 30 min | 20p/use | 14¢/use |
| Tumble dryer | 2,500 | 1 h | 66p/load | 45¢/load |
Heat the person, not the room. An electric blanket at 100 W costs about one-fifteenth of a 1,500 W space heater per hour. Swapping old incandescent Christmas lights for LEDs cuts their running cost by around 85%.
Electricity Cost Calculator FAQs
How do I calculate the cost of running an appliance?
Multiply watts by hours used and divide by 1,000 to get kWh. Multiply kWh by your price per kWh. The calculator does this and shows daily, monthly and yearly cost.
How much does a space heater cost to run?
A 1,500 W heater uses 1.5 kWh per hour: about 39p an hour at the UK price cap or 27¢ an hour at the US average rate.
What is the UK electricity price cap now?
For 1 October to 31 December 2026 the Ofgem cap averages 26.32p per kWh with a 54.83p daily standing charge (Direct Debit). Your region may differ slightly.
Are LED Christmas lights cheaper to run?
Yes, much cheaper. A typical LED set uses 5–30 W compared with 100–400 W for old incandescent strings.