About HexaCalc

HexaCalc is a free collection of 60 online calculators for the questions people actually search for every day: percentages, ages and dates, GPA and grades, loans, mortgages and retirement savings, and everyday math.

How we build our calculators

Every calculator is a small, deterministic function — no guesswork and no AI-generated numbers. Each one is covered by automated tests with hand-checked reference values (for example, a $25,000 loan at 7.5% for 60 months must return $500.95), and every page shows the formula, the steps and a worked example so you can verify the result yourself.

• Dates use exact calendar arithmetic, including leap years and month lengths.
• GPA calculations follow the standard US 4.0 scale, with common Honors/AP weighting and the LSAC scale for law school.
• Money calculators use standard amortization and time-value-of-money formulas and current IRS limits where relevant.
• Math expressions are parsed safely with standard order of operations (PEMDAS).

Privacy by design

Calculations run entirely in your browser. The numbers you type are not sent to our servers. See our privacy policy for details on analytics and advertising.

Not professional advice

Our financial, academic and age calculators provide estimates for education and planning. They are not financial, legal, tax or medical advice. Always confirm important decisions with a qualified professional or the official institution.

Contact

Found a bug or want a new calculator? Get in touch — we read every message.