Calculate the finish time of a marathon or half marathon based on your pace.
The Marathon Calculator predicts race time based on your current training pace or a shorter race result. The calculator uses the Riegel formula, which takes fatigue into account over long distances.
The calculator is completely free, works directly in your browser, and does not store personal information. All calculators on this site are up to date with 2026 information.
Predicted time B = Time A × (Distance B / Distance A)^1.06
Enter your measurements into the calculator fields and press the calculate button – the result will be displayed immediately. You can try different values to compare various scenarios.
10 km time 48 min → half marathon prediction = 48 × (21.1/10)^1.06 ≈ 106 min = 1:46:00.
The result is an estimate – for accurate clinical measurements, consult a healthcare professional.
The calculator is suitable for self-monitoring health, planning training, and general health literacy. Tracking values over time provides valuable information about changes in the body.
Remember that a single measurement result does not tell the whole story – what matters more is the direction and trend over multiple measurement periods.
Calculate the finish time of a marathon or half marathon based on pace. Fill in the requested information in the form, and the marathon calculator will show the result immediately.
Yes, the marathon calculator is completely free and does not require registration. All FiksuLaskuri health calculators are free of charge.
No. The calculations are done entirely in your browser and the data you enter is not sent or stored on the server.
No. The marathon calculator is a rough guide, not a medical diagnosis. For health-related decisions, it is advisable to consult a healthcare professional.
Yes – at the bottom of the page, you can see other calculators related to the same topic that may also interest you.