Free home energy tools · No sign-up
Calculate appliance electricity use and cost.
Use watts or measured kWh, your usage schedule, and your price per kWh to estimate appliance electricity cost. You can also inspect standby power and build a browser-local whole-home inventory.
- Seven supported currencies
- Your audit stays in this browser
- Transparent formulas
Illustrative example
Lab ready
Your resultestimated from entered inputs
ActiveActive use
StandbyStandby
Inputs you can
verify and edit
verify and edit
Full-precision math
rounded only for display
rounded only for display
YOUR RATE×YOUR HABITS×VISIBLE ASSUMPTIONS=A USEFUL ESTIMATE
01 · Quick calculator
Run the numbers.
Start with an illustrative appliance preset or enter wattage from its label or a meter. Active and standby inputs remain separate so you can see each part of the estimate. Need appliance-specific context? Browse the electricity-cost guides.
Comparison Lab
Compare entered energy scenarios.
This compares electricity inputs, not cooking performance, capacity, food quality, task suitability, or equal outcomes.
As entered compares independent annual schedules and does not assume equal service or output.
Correct both scenarios before comparing.
Enter two valid scenarios.
Equal use counts do not establish equal cooking results, capacity, quantity, quality, or task suitability.
02 · Your home audit
One home. The full picture.
Keep the existing standby audit or build a separate whole-home inventory. Both stay only in this browser.
Current household estimate
$0.00 per year
0devices
Active $0
Standby $0
Illustrative gross standby saving at 80% reduction$0 / yr
Before plug purchase and operating cost; assumes eligible standby consumption is reduced by 80%; not guaranteed. Includes only appliances marked Yes for safe scheduled disconnection and excludes No or Not sure.
Appliances0 added
Your audit is ready to build.
Calculate an appliance above, then add it here to see your household totals and hidden standby drain.
Add your first appliance →
Personalized action plan
0 actions
Add appliances to unlock recommendations.
Your action list will prioritize the largest costs and explicitly eligible standby loads.
Inventory results
0 items · 0 physical unitsUnnamed inventory
No modeled kWh yet.
Modeled appliances
Inventory items
| Appliance | Room/category | Basis/provenance | Quantity | Active kWh | Standby kWh | Total kWh | Annual cost | Actions |
|---|---|---|---|---|---|---|---|---|
| No inventory items yet. | ||||||||
By room
| Room | Items | Quantity | kWh/year | Cost/year |
|---|---|---|---|---|
| No data. | ||||
By category
| Category | Items | Quantity | kWh/year | Cost/year |
|---|---|---|---|---|
| No data. | ||||
By provenance
| Provenance | Items | Quantity | kWh/year | Cost/year |
|---|---|---|---|---|
| No data. | ||||
Optional reference
Compare modeled kWh with bill kWh
This is a coverage check, not a diagnosis. Do not enter the final bill amount.
No bill reference entered.
Use electricity consumption in kWh, not the amount due.
Differences can result from missing loads, heating or cooling, water heating, seasonal equipment, estimated readings, cycling, changed habits, or an unrepresentative billing period.
Largest modeled contributors
| Rank | Appliance | Room | kWh/year | Share |
|---|---|---|---|---|
| No contributors yet. | ||||
This inventory is an estimate of entered appliance electricity. It may omit central heating or cooling, water heating, pumps, outdoor equipment, shared loads, and seasonal use. Read the whole-home audit guide →
03 · Appliance directory
Where is your electricity going?
Explore transparent example inputs, usage patterns, standby behavior, and appliance-specific measurement guidance. Which appliances use the most electricity depends on their input power, runtime, cycling, quantity, and your home’s actual usage.
01
02
03
07
Heating & cooling
Seasonal schedules, compressor cycling, air movement, measurement, and safety.
Explore the cooling-cost guides ↗Kitchen
From always-on refrigeration to short cooking cycles.
Refrigerator guide · Air-fryer guide · Cooking comparisonsLaundry
See the cost per cycle and the impact of weekly habits.
Read the washing-machine guide ↗ 04Entertainment
Active viewing, sleep mode, and the devices around the TV.
Read the television guide ↗ 05Game consoles
Compare gaming, standby, and automatic power-down behavior.
Read the game-console guide ↗ 06Lighting
Model one ordinary LED bulb and account separately for connected controls.
Read the LED-bulb guide ↗Home office
Separate continuous network service from active, sleep, and charging modes.
Wi-Fi router guide · Laptop guideBrowse all appliance electricity guides Find your home’s largest modeled users with an inventory
The hidden bill
“Off” is not always off.
Televisions, consoles, printers, microwaves and chargers can quietly draw power all day. One device may cost little; a whole home of them can add up.
Open standby calculatorDoes unplugging appliances save electricity? Read the measured answer
●✦
Illustrative inputs: 5 W standby · 20 h/day · 7 days/week · $0.20/kWh
Annual energy
36.500 kWhAnnual cost
$7.30
Illustrative 10-year cost$73.00
10 years for 4 identical devices$292.00
Projection assumes unchanged wattage, schedule, device count, and electricity rate. Four devices means four identical devices under the same inputs.
04 · Our method
Estimates that explain themselves.
Energy calculators should not hide their assumptions. We show the inputs, formulas, sensitivity assumptions, and the quickest route to a more representative answer.
Use your real rate
Copy the price per kWh from your bill instead of trusting a generic national average.
Choose better inputs
A representative meter measurement can improve an active-use estimate. Label wattage and illustrative presets remain editable; standby must be entered or measured separately.
Test input sensitivity
We show a fixed illustrative band so you can see how predefined lower and upper multipliers change the answer.
THE FORMULA
watts × hours × days/week ÷ 7 × duty cycle × 365 ÷ 1,000 = annual
kWh
Try your numbers ↑