About RunCalc — Free Calculators for Everyone
RunCalc is a free online calculator site for running, fitness, finance, math, science, and unit conversions. 290+ tools, 37 languages, no account required.
Our mission
Free Calculators for Everyone
RunCalc is a free online calculator site for runners, students, households, and anyone who needs a quick answer. It started as a running pace tool and grew into 290+ calculators and converters for running, fitness, finance, math, science, dates, construction, cooking, and everyday unit conversions.
Direct Answers
What is RunCalc?
RunCalc is a free online calculator site at running-calculator.com. It offers calculators and converters for running pace, fitness, health, finance, math, science, dates, construction, cooking, and everyday unit conversions.
How does RunCalc work?
Choose a calculator, enter the values requested by the form, and the page calculates the result in your browser. Most tools show the formula or method used so you can understand the calculation, not just copy the result.
Is RunCalc free?
Yes. RunCalc calculators are free to use, with no paid tier required for normal calculator access.
Do I need an account?
No. You do not need an account, login, or email address to use RunCalc calculators.
What calculators does RunCalc offer?
RunCalc offers 290+ calculators and converters, including running pace calculators, race time predictors, BMI and calorie tools, mortgage and loan calculators, percentage and fraction calculators, date and time tools, construction estimators, cooking converters, and metric-imperial unit converters.
Our Story
RunCalc has existed since 2010 — back when the web was full of running calculators buried behind registration walls or cluttered with intrusive ads that obscured the one number you actually needed: your race pace.
We rebuilt the site from the ground up with a simple belief: a calculator should load fast, give you the right answer immediately, and get out of your way. No email required. No "premium tier." No dark patterns.
Over time, runners kept asking us for more — can you add a BMI calculator? A mortgage one? A time zone converter? So we did. Then 10 more. Then 100. Today RunCalc covers running, health & fitness, finance, math, conversions, date & time, construction, cooking, everyday life, and science. Every calculator is free to use.
We also believe calculators should work for everyone, everywhere. That's why we've localized major tools across 37 languages, with local units, currencies, and number formats where the calculator supports them. Whether you're in São Paulo, Seoul, or Stockholm, RunCalc speaks your language.
What We Stand For
Accuracy
Calculators use documented formulas, official standards, or established methods where applicable. Health and finance tools are informational and are not a substitute for professional advice. If you spot an error, tell us so we can review it.
Speed
RunCalc is a static site. No server round-trips, no heavy JavaScript frameworks, and no account gate before your result. Calculator forms run in your browser and are built to return answers quickly on phones, tablets, and desktops.
Privacy
Calculator inputs are processed locally in your browser and are not tied to a RunCalc account because no account is required. Standard page analytics or ads may measure visits where enabled, but calculator inputs are not collected as form submissions.
Accessibility
RunCalc is designed for broad access, with responsive layouts, keyboard-friendly forms, semantic labels where practical, and pages that work across common screen sizes and devices.
What You'll Find Here
RunCalc is best known as a running calculator — but it's grown into much more. Here's a taste of what's available:
- 🏃 Running calculators — Pace calculator, VDOT, race time predictor, marathon pace, half marathon pace, training zones, VO₂ max, treadmill converter, negative split, and more.
- 💪 Health & fitness — BMI, BMR, TDEE, body fat, macro calculator, calorie deficit, ideal weight, heart rate zones, and sleep calculator.
- 💰 Finance — Mortgage, compound interest, loan payoff, retirement planner, salary, investment returns, and debt-to-income ratio.
- 🔢 Math — Percentage, fractions, standard deviation, quadratic equations, probability, matrix operations, and 40+ more.
- 🔄 Unit conversions — Metric to imperial, temperature, currency, cooking measures, data sizes, and dozens of niche converters.
- 📅 Date & time — Age calculator, date difference, days until, time zone converter, business days, and pregnancy due date.