About Mathmatives
Mathmatives publishes free calculators, converters and browser tools for everyday tasks: checking numbers, writing notes, cleaning pasted text, planning time and working with HTML. There are no accounts or paywalls. Tool inputs are processed in your browser; advertising and hosting have separate data practices described in our privacy policy.
Our methodology
Calculator pages explain formulas, examples and assumptions. Browser tools describe supported input, saving and preview limits. Automated tests check selected examples and edge cases; they are not a professional audit of every possible result.
Editorial responsibility
Mathmatives is responsible for this site's content. We do not currently claim independent review by a qualified medical or tax professional. Where available, pages link primary references so you can check the underlying method. A content-update date records an edit, not expert approval. We do not publish invented authors, credentials or review dates.
Methods include amortization math for loans, the Mifflin-St Jeor equation for estimated resting energy, calendar-based pregnancy dating and cost-volume-profit analysis for business tools. Each has a limited scope. Primary references support the stated method, not a guarantee that an estimate fits your circumstances.
What these calculators are not
They are educational tools, not advice. Results are estimates based on the inputs and assumptions shown, and they cannot account for your full situation. For decisions with significant financial, legal or health consequences, use these tools to get informed, then confirm with a qualified professional.
Contact and corrections
Accuracy is the whole point of a calculator site. If you think a formula, example or explanation is wrong, or you have a question about the site, email mathmatives@gmail.com. We review every report.
Content updated .