Dehumidifier Running Cost Calculator

Enter the power rating shown on your dehumidifier and how long you expect to run it. The calculator uses your own electricity rate, so it stays useful even when tariffs change.

Appliance power (watts)Hours per sessionSessions per weekElectricity rate (pence/kWh)

Energy per session2.000 kWh

Cost per session£0.53

Weekly£3.68

Monthly estimate£15.97

Annual estimate£191.61

Formula: watts ÷ 1,000 × hours × electricity rate. This is an estimate; cycling appliances may draw less than their full rated power for part of the session.

What the result means

Actual power draw can vary by mode, room conditions and compressor cycling.
For the best estimate, use the wattage from the appliance label or a plug-in energy monitor.
The calculation covers electricity use only and does not include the purchase price.

Related guides

Read more about the topics covered by this calculator:

How this calculator works

Formula

Watts ÷ 1,000 × hours × electricity rate (pence/kWh) = cost in pence

Inputs

Appliance power in watts (from the label or energy monitor)
Hours per session
Sessions per week
Electricity unit rate in pence per kWh

Outputs

Energy per session (kWh)
Cost per session
Weekly cost
Monthly estimate (weekly × 52 ÷ 12)
Annual estimate (weekly × 52)

Assumptions

Rated wattage is used as the power draw throughout the session.
Actual consumption may be lower if the compressor cycles on and off.
Standing charges are excluded because they are payable regardless.

Example calculation

A 250W dehumidifier running 8 hours per day at 26.32p/kWh: 250 ÷ 1,000 × 8 × 26.32 = 52.6p per day, or roughly £3.68 per week.

Tariff source

Default rates are sourced from Ofgem's latest quarterly price cap determination. Users can override the rate in the calculator.

Limitations

Rated wattage can overstate real consumption for compressor types that cycle.
Desiccant dehumidifiers typically draw more power than compressor types.
Room temperature and humidity affect extraction rate and actual power draw.
This calculator estimates electricity cost only and does not include purchase price or maintenance.