Electricity Monitor
Choose a model for each appliance. Use measured average watts or energy per cycle when available: nameplate power is only an estimate, and actual use varies with settings and duty cycles.
Choose a model for each appliance. Use measured average watts or energy per cycle when available: nameplate power is only an estimate, and actual use varies with settings and duty cycles.
Illustrative inputs only. A cycling refrigerator rarely draws nameplate watts continuously. Separate pump and heater rows prevent assuming the same runtime. Before entering power in W, multiply any kW rating by 1,000: for example, a 2 kW heater is 2,000 W.
Daily: W × hours/day × quantity ÷ 1000; annual = daily × 365. Sessions: W × hours/session × sessions/week × 52 × quantity ÷ 1000 per year. Cycles: kWh/cycle × cycles/week × 52 × quantity per year. Monthly = daily × selected days. Use either measured cycle energy or watts for the same load, not both. No live meter, automatic appliance ratings, tariff lookup, standby or duty-cycle assumptions are provided. Costs exclude fixed charges and tiered tariffs. Before entering power in W, multiply any kW rating by 1,000: for example, a 2 kW heater is 2,000 W. Daily rows use 365 usage days per year. Weekly sessions and cycle rows use 52 weeks: seven sessions/week means 364 sessions, not 365. Per-use values include quantity; weekly values are shown for weekly/cycle rows. Custom-days monthly energy = annual/365 × chosen days; an evenly spread month = annual/12. For induction cooking enter minutes/session and sessions/week; for a fan use hours/session and operating days/week. Add each office device separately. An aquarium pump, heater and light can use three weekly rows with seven sessions/week and their own hours/session and watts. Immersion heaters and electric showers also use your own W rating (kW × 1,000), session runtime and weekly frequency. No typical wattage or duty cycle is inferred. Each row cost = its energy × your rate per kWh. Per-use, weekly and annual/12 costs use the same currency; weekly costs are only shown for weekly or cycle rows. These comparison rows use your cycle energy, separate tariff and chosen weekly frequencies. Cycle cost = energy × tariff; weekly cost = cycle cost × frequency; annual cost = weekly × 52. They are not added to appliance totals. No energy or frequency is prefilled.
| Scenario cycles/week | Cycle cost | Weekly cost | Annual cost (52 weeks) |
|---|
Blank voltage omits only equivalent Ah; energy and costs still calculate. If supplied, voltage must be positive and finite. Equivalent charge is daily kWh × 1,000 ÷ V, not battery sizing or a battery recommendation.
A QUICK WALKTHROUGH
How to use this tool
- Enter your electricity rate, currency, and days per month. System voltage (V, optional)
- Choose daily use, sessions per week, or kWh per cycle for each row. Add a pump and heater as separate rows with their own runtime.
- Compare annual energy and cost. Weekly models use 52 weeks; daily and monthly figures for them are averages over 365 days.
User-supplied estimate
This monitor uses only the wattage, hours, quantity, days, rate, and currency symbol you enter. It does not access a meter, utility account, tariff database, or appliance telemetry.
Three user-input models
Daily: W × hours/day × quantity ÷ 1000; annual = daily × 365. Sessions: W × hours/session × sessions/week × 52 × quantity ÷ 1000 per year. Cycles: kWh/cycle × cycles/week × 52 × quantity per year. Monthly = daily × selected days. Use either measured cycle energy or watts for the same load, not both. No live meter, automatic appliance ratings, tariff lookup, standby or duty-cycle assumptions are provided. Costs exclude fixed charges and tiered tariffs. Before entering power in W, multiply any kW rating by 1,000: for example, a 2 kW heater is 2,000 W. Daily rows use 365 usage days per year. Weekly sessions and cycle rows use 52 weeks: seven sessions/week means 364 sessions, not 365. Per-use values include quantity; weekly values are shown for weekly/cycle rows. Custom-days monthly energy = annual/365 × chosen days; an evenly spread month = annual/12. For induction cooking enter minutes/session and sessions/week; for a fan use hours/session and operating days/week. Add each office device separately. An aquarium pump, heater and light can use three weekly rows with seven sessions/week and their own hours/session and watts. Immersion heaters and electric showers also use your own W rating (kW × 1,000), session runtime and weekly frequency. No typical wattage or duty cycle is inferred. Each row cost = its energy × your rate per kWh. Per-use, weekly and annual/12 costs use the same currency; weekly costs are only shown for weekly or cycle rows. These comparison rows use your cycle energy, separate tariff and chosen weekly frequencies. Cycle cost = energy × tariff; weekly cost = cycle cost × frequency; annual cost = weekly × 52. They are not added to appliance totals. No energy or frequency is prefilled.
Daily equivalent charge (Ah)
Blank voltage omits only equivalent Ah; energy and costs still calculate. If supplied, voltage must be positive and finite. Equivalent charge is daily kWh × 1,000 ÷ V, not battery sizing or a battery recommendation.
GOOD TO KNOW
Common questions
Does this read my live electricity meter?
No. It is a browser-only estimate from your inputs.
Where does the electricity rate come from?
Enter the rate shown on your bill, contract, or another source you trust.