What is an age-grading percentage?
An age-grading percentage provides a way of measuring and comparing the quality of a running performance.
A calculation is carried out that takes into account the age and the sex of the runner and produces a single percentage value. This value can then be used to compare performances between males and females and across different ages and distances.
One useful application of age gradings is providing a fun and convenient way of allowing a simple comparison between runners that could not otherwise be competitive. So, it's possible to compare a 42-year-old woman's marathon, a 15-year-old boy's 5k, and a 66-year-old man's 10k.
Another application is allowing an individual runner to compare their own performances from previous years, or to estimate what they may have run when younger, or are likely to run when older. So, a 60-year-old who's been running for a few years could work out if their performances are improving over time despite slowing down in absolute terms. Or they could dream about what they might have run in their twenties.
A third application is helping individual runners to determine their best distance, or to identify elements of their fitness that are weaker and need work. E.g. a relatively lower age-grading for the half marathon compared to 5k and 10k could suggest that a runner needs to work on endurance (it is actually quite common for newer runners to perform relatively better over shorter distances, mainly because endurance takes many years to develop fully).
The higher the percentage, the better the performance. A value of 100% is generally considered the best that is possible for a particular distance by a runner of a specific age and sex. It is often, but not always, the value produced by the world record time.
Age gradings are calculated with reference to tables that have been compiled by considering a range of performances by male and female athletes of different ages. Find out how our calculator works »
Using the calculator
To use the calculator simply enter your age, sex, distance and time. You can choose from preset track or road distances or specify your own.
Note that the same time for the same distance will yield a different age grading according to whether it is run on the road or the track. Track races tend to result in better performances than the same distances run on the road (running tracks provide a high-quality surface, no hills, easy pacing and a relatively consistent environment with no surprises), and since the calculator is based on real-life performances, the age gradings reflect this.
How It Works
Your age-grading percentage can be used to objectively indicate your running standard. The table below is typically used:
Description of terms
The calculator generates several values in addition to the age-grading percentage. Understanding the terms used to describe these values helps explain how an age-grading percentage is calculated. This section may make more sense once you've got your own results in front of you.
This is the time achieved by the runner.
What qualifies as a senior athlete varies according to distance, sex and surface, but it is usually a range of ages somewhere between 19 and 34 years old.
For example, for 5km on the road, a male senior athlete is one aged 19 to 27; a female senior athlete is one aged 19 to 30. For the men's marathon, athletes are considered seniors if they are aged 19 to 31; for the women's marathon, it's 20 to 30. All track events for both males and females have a senior age range of 20 to 34.
Runners of ages above and below the range for senior athletes are considered at a disadvantage, and this is taken into account when determining their age-grading percentages.
The open-class-standard is the time for the specified distance and sex that will result in an age-grading percentage of 100% for a senior athlete. The open-class-standard can be thought of as the fastest possible time for a distance by an athlete of a specified sex.
The age-standard time is derived from the open-class-standard, and is the time for a specified distance and sex that will result in an age-grading percentage of 100% for an athlete of the specified age. It can be thought of as the fastest possible time for a distance by an athlete of a specified age and sex.
The age-factor is used to calculate the age standard from the open-class standard. It is a value equal to 1 or less. Specifically, the open-class-standard is divided by the age-factor to give the age-standard.
age-standard = open-class-standard / age-factor
Senior athletes are assigned an age-factor of 1, so their age-standard is the same as the open-class standard.
The age-graded time is the time for a senior that is considered equal in performance to the athlete time. It is calculated by multiplying the time achieved by the age factor.
age-graded time = athlete time * age-factor
The age-grading percentage is the value that indicates the quality of a performance and can be used for comparison. It is determined by dividing the age-standard time by the athlete time and converting the resulting proportion to a percentage:
age-grading percentage = age-standard time / athlete time * 100
The factors that are used to calculate age gradings are determined in different ways for track, road, and non-standard distances:
We calculate age gradings for road events using the tables maintained by Alan Jones. His web site contains detailed information about how the factors are derived and the tables are compiled and there are links to download the age-grading tables as spreadsheets.
Age gradings for track events are calculated using a mix of techniques.
For senior athletes (ages 20-34), percentages are calculated by direct comparison of a performance to current world senior records.
For athletes aged 35-100, the factors provided by WMA (formally WAVA) are applied to current senior world records to determine age standards, from which percentages are calculated.
For athletes aged 5-19, we derive our own factors using the age-group world records, compiled by Dominique Eisold and then apply these to current senior world records to compile a table of age-standards, which can be used to calculate percentages.
Our calculator allows you to enter any distance between 10 metres and 500 miles (804.67 kilometres). In order to determine age-grading percentages for these non-standard distances, linear interpolation is used to derive a factor between those for the two closest distances available in the relevant table.
Elite Age Gradings
You're not limited to calculating your personal age gradings. Some fun can be had by comparing world record performances.
Eliud Kipchoge vs. Brigid Kosgei
The men's and women's world marathon records are held by Kenyans Eliud Kipchoge and Brigid Kosgei.
Eliud Kipchoge set the men's marathon world record of 2:01:39 in September 2018, beating the previous world record by 1 minute 18 seconds. He performs consistently well and in October 2019 ran a sub-two-hour marathon in the Ineos 1:59 challenge (not recognised by IAAF as a world record). A quest that many believed impossible.
Brigid Kosgei claimed the women's marathon world record with a time of 2:14:04 in October 2019, beating Paula Radcliffe's long-standing marathon record by 1 minute 21 seconds. She has a string of marathon victories and medals behind her and is the youngest woman ever to win the London Marathon.
Kosgei set her record aged 25, and Kipchoge set his aged 33. Plugging their details into the calculator gives the following:
So, judging by age-grading percentage alone, it would appear that Kipchoge is the superior athlete with his result of 101.18% versus Kosgei's 101.01%
However, things are not so simple, and it could reasonably be argued that Kipchoge's performance is not the better of the two:
- The age-grading tables specify an age-factor of 0.9989 for 33-year-old male marathon runners, meaning that Kipchoge's performance is considered superior to that of a younger athlete, who would have to run 2:01:31 to achieve the same age-grading percentage. At 25, with an age-factor of 1, Kosgei does not benefit from an adjustment. In contrast to what the age-grading tables suggest, many would argue that endurance athletes in their early- to mid-thirties have an advantage over athletes in their mid-twenties.
- Open-class standards are typically set according to the world record at the time at which the tables are compiled. Kosgei is being judged against former world record holder Paula Radcliffe's 2004 performance of 2:15:25 whereas Kipchoge is being judged against Dennis Kimetto's (arguably softer) record of 2:02:39. Future age-grading tables will inevitably make adjustments based on these and other performances.
There are other good reasons that age-grading percentages in general are problematic when comparing different ages, sexes or distances. For example, fewer runners in a category means a smaller pool of talent from which to draw, and a less-competitive environment. This typically results in softer records and performances and therefore any age-grading tables compiled using these data will reflect that.
Age Grading Around The Web
It's quite common to see age-grading percentages and values published alongside results for races and runs. However, these are sometimes inconsistent. This may be because older tables are used, or, where tables are not explicitly available (e.g. for some ages and track events), the calculation is implemented differently. Some calculators round intermediate values, resulting in very slight differences. Details of how we calculate age gradings on runbundle are given above.
parkrun age-grading percentages
parkrun supply age-grading percentages alongside each runner's results
They do not make their age-grading tables publicly available, but state that they are loosely based on those produced by WMA.