Age grading compares a performance with a reference standard for the athlete's age, sex, and event. The quality of the result depends entirely on the reference table used.
Why RunCalcs removed its former factor table
The previous CSV used smooth editorial factors described as “WMA-style.” They were not the official one-year World Masters Athletics factors and could therefore produce percentages that looked authoritative without being reproducible from the governing body's tables.
RunCalcs no longer distributes those factors. This page now explains the method and links directly to the authoritative documents. The marathon pace chart by age provides a different, clearly sourced comparison using official Boston qualifying standards.
What an age-grade percentage means
For a running event, the percentage compares the athlete's time with an age-and-sex standard for the same distance. A higher percentage represents a performance closer to the reference standard.
Age grading is useful for tracking an athlete over time and for comparing performances within the same grading system. It is not a medical measure, a prediction of future potential, or proof that performances in very different events are equivalent.
How running age grades are calculated
Age-grade percentage = 100 × age-and-sex standard time ÷ athlete time.
Both times must use the same units. For example, if the applicable standard is 2,400 seconds and the athlete runs 3,000 seconds, the age grade is 100 × 2,400 ÷ 3,000 = 80.0%.
The example demonstrates the arithmetic only. A valid calculation requires the correct official standard for the athlete's exact age, sex, event, and table edition.
Use authoritative factors
World Masters Athletics first adopted age-grading factors in 1989 and periodically updates them. WMA says its 2023 update used age-best performances plus more than 2.8 million additional performances. For combined events, use the current WMA Appendix B factors. WMA's competition documents page separately lists road age standards.
Do not interpolate a homemade percentage from decade-level factors when an official one-year table exists. Record the table edition with every published result so the calculation can be repeated later.
Limitations
- Different table editions can produce different results for the same performance.
- Road, track, and combined-event tables are not interchangeable.
- Course certification, elevation, surface, weather, and timing method still affect the underlying performance.
- Age-grade percentages are modelled comparisons, not observed percentiles of all runners.
- Comparisons are most defensible when athletes use the same table edition and event definition.
Continue with race-performance tools
Primary sources
Editorially source-checked: July 18, 2026. RunCalcs does not reproduce unofficial age factors on this page.