DIY Cost Tools
Dehumidifier Electricity Cost Calculator
Estimate monthly and annual electricity use for a dehumidifier from its wattage, daily run time and utility rate.
How to use this calculator
- Replace every example value with your own measurements, label values or planning assumptions.
- Keep each value in the unit printed beside its field.
- Select Calculate, then compare the result with the formula and limitations below.
Formula and method
Monthly kWh = watts ÷ 1,000 × hours per day × 365 ÷ 12. Monthly cost = monthly kWh × utility rate; annual cost = monthly cost × 12.
Results are hidden whenever an input changes or validation fails, so an older answer cannot be mistaken for the current calculation.
Worked example
Rated power = 500 W; Average run time = 8 hr/day; Electricity rate = 0.16 $/kWh. The calculator returns Monthly energy = 121.7 kWh; Monthly cost = 19.47; Annual cost = 233.6.
The worked example uses the same default values displayed in the calculator.
Limitations and safety
Frequently asked questions
What should I enter first?
Start with measurements or rates from the project, product label, service quote or equipment specification. Replace every example value before relying on the estimate.
Why can the real result differ?
Actual cycling depends on humidity, temperature, airflow, filter condition and moisture sources. EPA advises fixing moisture problems and generally keeping indoor relative humidity below 60%, ideally 30%–50%.
Does the calculator round purchases up?
Only outputs labeled as whole packages, vents, heaters, pails or similar counts are rounded up. Keep extra precision for planning and follow supplier packaging.
Review notes and reference
Reviewed October 5, 2026. The formula was independently checked against the displayed default example, and the calculator was tested for valid defaults, empty input, invalid formats, range boundaries and recovery. Reference: EPA Mold, Moisture and Your Home. Explanations and examples are original.