How age grading works
Age grading normalizes performances across age and sex so they can be compared on one scale. A 60 year old's 5K and a 25 year old's 5K are different physical feats, and raw times cannot tell you which was the better run. Age grading can. Each combination of sex, event, and age has a factor: 1.0 through the prime years, declining gradually after about age 35 (and rising toward 1.0 through childhood on the young side). Multiply your actual time by that factor and you get your age-graded time, the open-class equivalent of your performance. Divide the open-class standard for your event by that time and you get your age-graded percentage, where 100 percent is world-record level for your age and sex.
The key property is that the same percentage means the same relative quality at any age. A 68 percent 10K at age 55 and a 68 percent 10K at age 28 represent the same level of running, which is why age grading is the standard way clubs score cross-generation competitions: everyone races their own event and their own body, and the percentages settle who ran best.
The data behind this calculator
This calculator uses the 2025 WMA / USATF MLDR road age-grading tables compiled by Alan Jones, the current edition, approved by the Masters Long Distance Running Council of USA Track and Field in January 2025. The convention is the standard one: age-graded time equals your time multiplied by the age factor, and the percentage equals the open-class standard divided by that age-graded time. The tables cover road events only; track age grading uses separate tables with different factors. One detail worth knowing for ultrarunners: in the 2025 tables, all ultra distances from 50K up share the marathon factor curve, and only the open-class standards differ between those events.
What the percentages mean
| Age grade | Level |
|---|---|
| 100%+ | World record level |
| 90%+ | World class |
| 80%+ | National class |
| 70%+ | Regional class |
| 60%+ | Local class |
Worked example: two runners, two decades apart
Take a 50 year old man who runs a half marathon in 1:40:00. His age factor is 0.8860, so his age-graded time is 1:28:36, and his percentage works out to 64.9 percent, local class. Now take a 60 year old woman who runs a 5K in 28:00. Her factor is 0.7621, her age-graded time is 21:20, and her percentage is 65.1 percent, also local class. On raw times these two performances are hard to compare; age grading shows she actually edged him out, and it shows both of them exactly where they stand relative to the best runners of their own age and sex.
Related tools and guides
Your age-graded equivalent time plugs neatly into the race time predictor to project fitness across distances, and the pace calculator turns any target time into per-mile and per-kilometer splits. To convert a recent result into daily training paces, use the training pace calculator.
Frequently asked questions
What is a good age grade percentage?
Anything over 60 percent marks a solid club runner, over 70 percent is strong and competitive at the regional level, and over 80 percent is exceptional, the range where national-class masters athletes live. Above 90 percent is world class, and 100 percent means an age-group world record level performance. Most healthy recreational runners who train consistently land somewhere in the 50 to 70 percent range.
How do the tables handle very young runners?
The 2025 road tables cover ages 5 through 100, and factors below the prime years work the same way they do for masters: a factor below 1.0 reflects that a 10 year old cannot be expected to match an open-class adult. This calculator accepts ages from 5 to 100 and truncates fractional ages to whole years, matching how the published tables are indexed.
Why did my age grade percent change when the tables updated?
The tables are revised periodically as age-group world bests improve. The 2025 edition superseded the 2020 tables, and any revision shifts factors and open standards slightly, so the same race can score a point or two differently under the new edition. Your fitness did not change; the yardstick did. Compare performances scored under the same edition when you can.
Is this the official WMA calculation?
Yes. This calculator uses the current 2025 WMA / USATF MLDR road age-grading tables compiled by Alan Jones, applied with the standard convention: your time multiplied by the age factor gives the age-graded time, and the open-class standard divided by that time gives the percentage. It is the same math the reference calculators and most race scoring software use.
Does age grading work for ultramarathons?
Yes, for the road ultra distances in the tables: 50K, 50 miles, 100K, and 100 miles. One quirk worth knowing: in the 2025 tables, every ultra distance from 50K up shares the marathon age-factor curve, and only the open-class standards differ between events. That is how the source publishes the data, so your factor at a given age is identical for the marathon and a 100 miler.