About Plainsum

Plainsum is a free collection of calculators for everyday money, life, and health questions. Every tool runs in your browser, explains its formula in plain English, and asks for no account or personal details.

How we build calculators

Each calculator uses standard, published formulas, such as the amortization formula for loans and the Mifflin-St Jeor equation for calories. We test results against worked examples and note the assumptions on each page.

Limits

Results are estimates for general information. They are not financial, tax, legal, or medical advice, and they don't account for every rule or personal circumstance. Please confirm important decisions with a qualified professional.

Contact

Found a mistake or want a new calculator? Email hello@example.com.