Dehumidifier vs Tumble Dryer Calculator
Compare the electricity used to dry an equivalent laundry load with a dehumidifier and a tumble dryer. Use your own drying time and energy readings to see what repeated loads cost.
How to use Dehumidifier vs Tumble Dryer Calculator
1. Choose the currency used for results. 2. Enter the dehumidifier’s average watts and hours needed for one load. Enter measured tumble-dryer kWh for an equivalent load dried to a similar standard. 3. Change a value to update the results, or select Calculate. Review the chart and notes with the total. 4. Use Copy results, Share results or Download result graphic to keep the answer. Shared links include your figures. 5. Reset restores the editable example inputs.
Why use this tool?
A small power draw does not guarantee a cheaper dry if the appliance runs for many hours. Comparing the total energy for one laundry load is more useful than comparing two wattage labels. Room conditions matter for a dehumidifier: ventilation, temperature, humidity and the way laundry is hung can change the time needed. The calculator lets you use the time you have observed. It does not predict when clothes will be dry or assume that two loads are equivalent just because they have the same weight.
How the calculation works
Dehumidifier energy per load = average watts ÷ 1,000 × hours per load. Tumble-dryer energy per load is the kWh you enter. Multiply each by the same electricity price for its per-load cost, then by loads per week × 52 for a yearly comparison. Purchase cost, extra room heating, ventilation and any indirect effect on household heating are excluded. These can matter to a real choice, but should not be invented from an appliance’s power alone.
Example
A dehumidifier averaging 250 W for eight hours uses 2 kWh. A tumble dryer using 2 kWh for the same laundry load has the same direct electricity cost: £0.50 at an illustrative £0.25/kWh. Shortening the dehumidifier run to four hours would halve its entered electricity use.
Practical tip
Measure a few representative loads. A damp towel load and a small load of lightweight clothes can need different amounts of energy and time.
Frequently asked questions
Is a dehumidifier always cheaper for drying clothes?
No. The result depends on its power and how long it takes, compared with the energy used by the dryer. Use equivalent loads and observed drying times.
Why does the dryer use kWh rather than its wattage?
A complete cycle can change power as it runs. Measured energy for the whole cycle includes that variation, while a maximum rating multiplied by the full time can overstate use.
Does the comparison include buying either appliance?
No. It compares direct electricity costs. Purchase price and any additional heating or ventilation costs would need a separate ownership or payback calculation.