This heated throw vs electric heater calculator compares the electricity cost of two usage scenarios. Enter each appliance’s power, its element-on percentage, your tariff and shared hours of use. You will see the daily and period costs plus the difference.
A heated throw warms the person using it; a room heater supplies heat to the room. A cheaper calculation does not mean they provide an equivalent service. A throw may suit sitting still in an adequately heated room, but this tool cannot tell you whether a room is warm enough or whether its heating can safely be reduced.
Heated throw vs electric heater cost calculator
Enter your own tariff and appliance ratings
The 25p/kWh starting value is an illustration, not a current tariff quotation. Both appliances use the same hours per day in the comparison.
Enter your figures and select Calculate running cost.
Use the rating on your own appliances
The initial 100W throw and 2,000W heater are examples, not specifications for every product. Check each label or manual. A 150W throw should be entered as 150, and a 1.5kW heater as 1,500. The tariff field takes pence per kWh: enter 25 for 25p/kWh. That starting rate is illustrative, not a current tariff quotation.
The element-on percentages allow for heating controls switching on and off. A value of 100% assumes the appliance draws the entered power throughout the session; 50% assumes half the time. These are your assumptions, not measurements. A low temperature setting does not necessarily correspond to a particular percentage.
Both appliances use the same hours-per-day input for this comparison. If you use a throw for two hours and a heater for four, calculate each separately with the appropriate hours and compare the costs you record. The period result assumes the same daily pattern for the number of days entered.
Worked example: four hours per day
| Scenario at 25p/kWh | Daily energy | Daily cost | 30-day cost |
|---|---|---|---|
| 100W throw, 100% element-on, four hours | 0.4kWh | 10p | £3 |
| 2,000W heater, 50% element-on, four hours | 4kWh | £1 | £30 |
| 2,000W heater, 100% element-on, four hours | 8kWh | £2 | £60 |
The first two scenarios differ by £27 over 30 days. That is an arithmetic comparison under the stated assumptions, not a promise of savings. If the room heater continues running unchanged while you add a throw, the throw adds consumption. Savings arise only when the overall heating pattern actually uses less energy.
How the calculation works
For each appliance: kWh per day = watts ÷ 1,000 × hours × element-on percentage ÷ 100. Multiply by the electricity price in pounds per kWh for the daily cost, then by the days for the period cost. The difference shown is heater cost minus throw cost; a negative result means the throw scenario costs more.
The calculator leaves out standby loads and the standing charge. It assumes a single unchanged unit rate, so split a time-of-use tariff into separate periods if needed. It does not include purchase prices, replacement costs or the cost of any other heating that remains on.
Personal warmth and room warmth are different jobs
A throw can be useful when one person is sitting on a sofa or at a desk and wants extra warmth. It does not distribute room heat in the way a space heater does. Other people, cold surfaces and the building’s heating needs still matter. Do not make a blanket or throw your sole response to an inadequately heated home.
For decisions about heating the room itself, read our guide to 2kW electric heater running costs and our oil-filled radiator versus fan heater comparison. They explain power, running time and format choices. Browse Heating guides for buying guides and Energy & Running Costs guides for budgeting help.
Use heated textiles as their instructions require
Check for damage and follow the product’s instructions for positioning, washing and storage. Do not operate a heated textile folded or creased, or with a hot-water bottle. Electrical Safety First’s saving-money-safely advice includes electric blanket precautions. A heated throw, underblanket and overblanket are not interchangeable; use only as the maker intends.
For the room heater, follow its clearance and socket instructions, keep it uncovered, and switch it off before leaving it unattended or sleeping. This cost tool does not override any manufacturer’s safety instructions.
Frequently asked questions
Does a heated throw always cost 10p for four hours?
No. That example assumes a 100W draw throughout, a 25p/kWh tariff and four hours of use. Different ratings, control cycling, hours or unit rates change the answer.
Can I count the calculator difference as guaranteed savings?
No. Use it to compare assumptions. Your actual saving depends on the heating you reduce, whether that remains appropriate for the household, and the real energy used by both appliances.
