Age-Graded Running Time Calculator
What would a 25-year-old have to run to match what you just ran at 50? Hold the age-graded percentage constant and the answer is arithmetic. Enter your time and the two standard times, all in minutes:
Equivalent time at the target age/sex
48.4 min
Same age-grading percentage as your actual time in the source event.
The formula
Equivalent time = your time × (target standard ÷ your standard)
Both standards come from the same table, for the same distance: one for your age and sex, one for the age and sex you are translating to. Because the age-graded percentage is standard ÷ time, the two percentages come out identical by construction. Look the standards up first — the pillar page explains where the percentage itself comes from.
Two worked examples
Same sex, different age. A 50-year-old man runs 10K in 42:00. In the 2025 tables his standard is 29:43 and a 25-year-old’s is 26:24 (the open standard, since the factor is 1.000 through the twenties).
42:00 × (26:24 ÷ 29:43) = 37:19
Both times score 70.7%. The younger runner has to be almost five minutes faster to be doing the same thing.
Same age, different sex. A 40-year-old woman runs 10K in 40:00. Her standard is 29:54; a 40-year-old man’s is 27:24.
40:00 × (27:24 ÷ 29:54) = 36:39
Both score 74.7%. Note how much smaller the sex adjustment is than the 25-year age gap in the first example — at 10K the age curve is steeper than the sex gap once you are past 50.
Where the translation is honest, and where it is not
It is honest as a comparison of relative level. It is not a forecast: nothing in the table knows your training history, and a real 25-year-old version of you might have run faster or slower than 37:19. Nor does the conversion transfer across distances — the standards for 5K, 10K, the half and the marathon are built separately from single-age bests, and everything else is interpolated between them, so a 10K equivalent tells you nothing directly about a marathon.
The standards themselves, for those four distances and a range of ages, are laid out in the age-grading tables, and the naming question — why the same number is called the WMA percentage — has its own page.
Frequently asked questions
What is an age-adjusted equivalent time?
The time a runner of another age or sex would have to run, at the same distance, to earn the identical age-graded percentage you did. It is a translation between two reference frames, not a prediction.
How is the equivalent time calculated?
Equivalent time = your time × (target standard ÷ your standard). Both standards come from the same table, for the same distance, so the percentage on each side of the equation is identical.
What is it used for?
Handicap scoring in open races, comparing yourself with a training partner of a different age or sex, and tracking whether your own relative level is rising even as the clock time slows.
Does it predict what I will run at that age?
No. It says what time would represent the same relative level, using population standards. Your own trajectory depends on training, health and injury history, none of which the table knows about.
Which standards does it use?
The 2025 road tables approved by the USATF Masters Long Distance Running Council on January 10, 2025, with standards built for 5K, 10K, half marathon and marathon and interpolated for other distances.
Sources
- Jones A, Harvey R. Age-Grade Tables — 2025 road standards, approved by the USATF Masters Long Distance Running Council (CC0)
- USATF Masters — Age Grading
Written by Lucas Silva · Reviewed by Lucas Silva · Updated on August 15, 2026