W · kWh · Energy cost
Electricity Cost and Energy Calculator
Estimate appliance electricity costs, compare tariffs and explore savings. Plan household energy use with clear formulas, charts and downloadable results.
Billing settings
Use prices from your bill. Currency changes formatting only, not exchange rates. Off-peak allocation is an estimated share of all energy. The tier limit applies to the combined period total; device costs are allocated proportionally, not as marginal prices. Add tax only if your prices exclude it.
Your appliances
Enter uses, not usage days: two uses a day for 30 days means 60 uses. In power mode, standby applies to all remaining hours, assuming the device stays plugged in. Measured and label values already include recorded consumption; no extra standby is added. Annual labels use 365 days.
Presets are editable examples, not measured specifications. Use real wattage or energy-label data, and enter your own local emissions factor to estimate CO₂e. Leaving it blank disables the estimate. Decimal commas or points are accepted; do not use thousands separators.
Check the highlighted fields. Values must be non-negative; days and quantities must be integers. Operating hours per device cannot exceed 24 × period days. You can add up to 20 appliances.
Cost for selected period
All projections repeat the selected period: daily = period total ÷ days; weekly = daily × 7; annual = daily × 365; monthly = annual ÷ 12. Fixed fees repeat at the same frequency. These are averages, not seasonal forecasts.
Summary
- Energy cost
- Fixed fee per period
- Added tax
- Total
| Appliance name | Energy for selected period | Standby energy | Energy cost | Share of energy | Energy cost per use | Energy cost per operating hour |
|---|
Cost by appliance
Energy distribution
Cumulative cost
Charts show energy charges; the fixed fee is separate. Cumulative cost assumes evenly distributed usage and charges the fixed fee at the start. Per-use and hourly costs are for one device, including added tax but excluding standby and fixed fees. Zero consumption has no percentage distribution.
Formula and calculation
Compare and save
This independent comparison uses one constant, tax-inclusive energy price. Standby assumes year-round connection outside operating hours. Payback = extra purchase cost ÷ annual savings; it excludes financing, maintenance and future price changes. Non-positive savings have no payback.
Check the highlighted fields. Values must be non-negative; days and quantities must be integers. Operating hours per device cannot exceed 24 × period days. You can add up to 20 appliances.
Formula and calculation
Method and assumptions
Consumption method
Enter uses, not usage days: two uses a day for 30 days means 60 uses. In power mode, standby applies to all remaining hours, assuming the device stays plugged in. Measured and label values already include recorded consumption; no extra standby is added. Annual labels use 365 days.
Method and assumptions
All projections repeat the selected period: daily = period total ÷ days; weekly = daily × 7; annual = daily × 365; monthly = annual ÷ 12. Fixed fees repeat at the same frequency. These are averages, not seasonal forecasts.
Tariff
Use prices from your bill. Currency changes formatting only, not exchange rates. Off-peak allocation is an estimated share of all energy. The tier limit applies to the combined period total; device costs are allocated proportionally, not as marginal prices. Add tax only if your prices exclude it.
Compare and save
This independent comparison uses one constant, tax-inclusive energy price. Standby assumes year-round connection outside operating hours. Payback = extra purchase cost ÷ annual savings; it excludes financing, maintenance and future price changes. Non-positive savings have no payback.
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