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Run the numbers. Then run easy.

Split tables, a gel planner, a race predictor and the World Marathon Majors. Built for a phone at the start line, with every formula written out underneath.

Example: a 3:30 marathon
finish
3:30:00finish
per km
4:59/km
per mile
8:01/mi
km/h
12.1km/h · 7.5 mph
See every split →

Tools

  1. Pace tableGoal time in, split table out. Even or negative, km or miles, printable pace band.
  2. Pace convertermin/km, min/mile, km/h and mph, with finish times for the big four distances.
  3. Nutrition plannerCarbs per hour in, gel count and a timed schedule out. Fluid and sodium ranges included.
  4. Race predictorA recent race result in, predictions for other distances out, with the caveats spelled out.

The Majors

Tokyo, Boston, London, Sydney, Berlin, Chicago and New York: course profiles, dates and how to get a bib.

All seven Majors

How the numbers work

  1. Formulas on the page

    Each tool explains what it calculates and where the method stops being reliable. No black boxes.

  2. A source for every spec

    Shoe and race facts link to where they came from. If a value can't be verified, it says so instead of guessing.

  3. Your data stays yours

    No accounts, and analytics only if you agree. Results live in the page link, so sharing a plan means sharing a URL.