LifeCost

More in Daily Frugality

What this calculator does

Each degree of heating or cooling changes your utility bill. This calculator uses a rough 3% rule of thumb.

The math

Monthly savings = base bill × 0.03 × degrees changed.

Worked example

A $150 base bill with a 3-degree adjustment saves about $13.50 per month.

Why this matters

Small daily habits are the easiest to change and the fastest to compound. This calculator shows the real savings from one swap.

Methodology and transparency

This page publishes the exact formula used to compute the result, so you can verify it in a spreadsheet or check the assumptions against your own situation. The worked example uses the tool default inputs; change any number and the result updates live in your browser. No data is sent or stored.

Common questions

Is 3% per degree accurate?

It is a rough estimate. Real savings depend on climate, insulation, and HVAC efficiency.

Should I change the thermostat by a lot?

Even 1–2 degrees can save money without much discomfort.

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