About PocketMath

Useful math for everyday decisions.

PocketMath is an independent collection of free calculators operated by Fumiya Kobayashi in Japan. It helps you check small calculations without creating an account or installing an app.

How the tools work

The calculators use the formulas explained on the home page. Amounts are displayed to two decimal places. They do not connect to bank accounts, process payments, convert currencies, or provide financial advice.

Advertising

PocketMath includes Google AdSense code to support the site through advertising. Advertisement availability depends on Google and may vary by visitor. The tools remain available without a subscription.

Contact

Report a calculation issue or ask a privacy question at fmfm.stars@gmail.com. When reporting an issue, include the calculator name, your example inputs, and the result you expected. Do not send card numbers or sensitive account information.