Electrical Calculator
Electricity Cost Calculator
Estimate electricity usage and cost based on power, daily usage time, number of days, and electricity rate.
What this calculator does
This calculator provides a simple electricity cost estimate using device power, daily operating time, number of days, and a flat electricity rate per kWh.
It is useful for quick estimates involving appliances, office equipment, small machines, lighting loads, or rough monthly energy cost checks.
Inputs
Result
How to read the result
The energy result shows how much electricity the load is expected to use over the selected period. The cost result is a simple estimate based on the rate you entered.
This is most useful for rough comparison, budgeting, and quick usage checks. It should not be treated as an exact utility bill prediction.
Formula
Energy (Wh) = Power (W) × Hours per Day × Days
Energy (kWh) = Energy (Wh) ÷ 1000
Cost = Energy (kWh) × Rate per kWh
Example
If a device uses 500W for 5 hours a day over 30 days:
500 × 5 × 30 = 75,000 Wh
75,000 Wh ÷ 1000 = 75 kWh
If the rate is 140 per kWh, then cost = 75 × 140 = 10,500
Important notes
This is a flat-rate estimate
Many real electricity billing systems use tiered pricing, taxes, demand charges, or fixed fees. This page does not include those details.
Actual usage may vary
Some devices do not run at their rated power continuously. Real energy consumption may be lower or higher depending on operating conditions.
This is a quick reference tool
Use this calculator for simple comparison and estimation, not final utility billing verification.
FAQ
Does this include tiered electricity billing?
No. This is a simple estimate using a flat rate per kWh.
What unit should I enter for the rate?
Enter the cost for 1 kWh in your local currency or billing unit.
Can I use this for monthly estimates?
Yes. The default value is 30 days to make monthly estimation easier.
Why can the real bill differ from this result?
Real utility billing may include tiered pricing, service fees, taxes, and differences between rated and actual equipment consumption.