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Electricity bill detective

Why did my electricity bill go up? Separate usage from price.

Compare two bills and see whether the change came from using more electricity, a higher unit price, or fixed charges.

Instant estimate · ✓ No sign-up

Editable example — replace it with your real numbers.

How this estimate works

How this estimate works

We subtract fixed fees, calculate the effective price per kWh for each bill, then split the total difference into usage, price and fee effects. Taxes and tiered tariffs can make the split approximate.

All formulas and assumptions

Quick answers

Where do I find kWh?

Look for consumption, usage or kWh on each bill.

Can I use bills with different periods?

Compare bills covering the same number of days. Otherwise the result can be misleading.

Why can the parts differ slightly from the total?

Rounding, taxes and tiered tariffs may not divide perfectly into one unit price.