About PaceSplit
Sixteen running calculators, every formula sourced, no accounts and no tracking.
PaceSplit exists because most online running calculators answer the question and stop there. We wanted a place that answers the question and shows the working: which formula produced the number, where the formula comes from, and where it stops being reliable. Every calculator on the site is built around that idea — give the runner the result they came for, then tell them enough about the math to trust it (or to know when to push back).
The formulas are not ours. We use peer-reviewed work from sport scientists and coaches whose names you’ll see on the Methodology page — Daniels & Gilbert for VDOT, Riegel and Cameron for race-time prediction, Karvonen for heart-rate zones, Jones & Doust for treadmill grade adjustment, and so on. Each calculator’s page lists the specific source it relies on so you can read the original research if you want to.
There are no accounts to create, no contact form, no analytics, and no cookies — see the Privacy Policy for the long version. Calculator preferences live in your browser only. The site is deliberately small in scope: a focused set of runner-facing tools, kept simple and kept fast.