What is age grading in running?
A percentage comparing your time with the world-best time for your age and sex, so runners of different ages can be compared fairly.
Age grading expresses your race time as a percentage of the world-best standard for your age and sex at that distance. A 70% age grade means you ran a time that is 70% as fast as the best ever recorded by someone of your age and sex — a genuinely strong club-level performance, not a modest one.
It exists because raw times are a poor basis for comparison across a field. A 3:30 marathon by a 30-year-old and a 3:30 by a 60-year-old are entirely different achievements, and age grading makes that visible in one number.
The standards come from World Masters Athletics tables, which are updated periodically as records change. The underlying decline is not linear: performance falls slowly through the late thirties and forties, then more steeply past 50 and steeply again past 70, which is why a piecewise model fits better than a single annual percentage.
The most valuable use is longitudinal. Tracking your age grade over years separates genuine fitness change from the background decline that happens anyway, and it is often much more encouraging than watching raw times drift.
Key numbers
| Decline 35–50 | ~0.4% per year | |
|---|---|---|
| Decline 50–70 | ~0.7% per year | |
| Decline 70+ | ~1.1% per year |
Work it out for yourself
Race time predictor — Age-grade your results and see equivalent times at other ages.
Frequently asked questions
What is a good age grade?
As a rough guide: above 60% is a solid local-club standard, above 70% is regional class, above 80% is national class, and above 90% is world class. Most recreational runners sit somewhere in the 45–65% band, which represents perfectly respectable running.
At what age do runners slow down?
Measurable decline generally begins in the late thirties, but it is gentle at first — well under half a percent a year — and easily outweighed by training improvements. It steepens after about 50 and again after 70. Many runners set marathon personal bests in their forties simply because that is when they finally train consistently.
Sources
- Tanaka & Seals (2008). Endurance exercise performance in Masters athletes. Journal of Physiology.
- World Masters Athletics age-grading tables.
Related explainers
Glossary: VO₂max