Disclaimer

Last updated: September 2026. Please read this page carefully before using our calculators.

Educational information only

All content on PaceKeeper — calculators, articles, tables, and examples — is published for general educational purposes. It is not training advice and is not a substitute for a qualified professional. We are not physician before beginning a strenuous training programs, and no client or advisory relationship is created by your use of this Site.

Race predictions extrapolate from your current fitness; training zones derive from formulas, not your laboratory-tested physiology. Heat, hills, fatigue, and biomechanics move real-world paces well off any table. Treat outputs as planning guides — and adjust by feel and results.

Chest pain, dizziness, or unusual shortness of breath during running is a stop signal and a medical conversation, not a pacing problem.

Accuracy of calculations

We implement well-known, publicly documented formulas (see the methodology section on each calculator page and published exercise-physiology research (Riegel, Daniels) as applicable). Even correctly implemented formulas produce estimates that depend on your inputs and assumptions. Real-world outcomes vary. Do not rely on a single web tool for a consequential decision.

Advertising disclosure

PaceKeeper is funded by display advertising served through Google AdSense. Advertisers have no influence over our content, formulas, or editorial choices, and placement of an ad is not an endorsement.

Errors and corrections

If you spot an error, please email hello@pacekeeper.app with the inputs you used. Verified corrections are published promptly.