Running Age-Graded Calculator: Analyse, Compare, & Predict

Welcome to Marathon Handbook’s age-graded running calculator.

By inputting a previous race time, your age, and your gender, you can:

  • Compare your run times to other people regardless of age and gender using the age grade score.
  • If you are younger than 20 or older than 30, you can use the age-graded time to view the equivalent speed you would have run if you were within this age range.
  • View predicted race times for all common race distances.

Scroll past the age-graded calculator itself to view a detailed breakdown of how the calculator works and what exactly the results mean.

You can also check out our advanced marathon race time prediction tool for a highly accurate marathon time estimation, or, take a look at our classic race time prediction calculator to see a wider range of race time prediction methods.

Age Grading Calculator

Age-Grade Calculator

*Please enter an age between the ages of 10 and 100.

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Age Factor:
The age factor is a coefficient that adjusts performance based on age and gender.

Age Graded Result:
The age-graded result is your time adjusted by the age factor. It is a prediction of how fast you would have run if you were between the ages of 20 and 30 (known as the open class).

Age Graded Score:
The age-graded score is a percentage showing the ratio of your age-graded result to the world record for your age and gender. It can be used as a tool of comparison across all ages and genders.

Predicted Times

This calculator uses 2020 age-graded and world-record data published by Alan Jones, under Creative Commons Zero v1.0 Universal licence.

How Does The Age-Grade Calculator Work?

What Is Age-Grading?

Age-grading is a way of analyzing running performance relative to your age or gender.

Age-grading is based on world record race time data, from which it attempts to estimate the best possible time an athlete can run a certain distance based on their age and gender, using a specific number between 0 and 1 called an age factor.

Besides comparing performance and predicting race times, other uses of age grading include assessing your own performance realistically based on your age and gender, setting race goals (e.g. how well do you want to perform relative to your age), and comparing performance to your younger self.

Our calculator is built on the most recent 2020 USATF-approved age-factor data.

Age Factors

For each race distance, there are a number of age factors, with each age factor corresponding to a particular age and gender.

Therefore, when the calculator user inputs their age, gender, and race distance, this corresponds to a particular age factor.

Overhead view of a running race

Age Graded Result

From this, the age grade calculator calculates the user’s age-graded result by multiplying the user’s finish time for the known race distance by their age factor.

It can be considered as an age-adjusted running time.

For users who are between the ages of 20 and 30 years old (known as the open class), their age factor is 1, meaning that their age-graded result will be the same as their actual finish time (as their finish time is just multiplied by 1).

The open class signifies the age range in which runners tend to have the highest level of running performance, therefore their race time doesn’t need to be adjusted in order to account for their age, hence an age factor of 1.

The age-graded result effectively means the equivalent time you would have run if you were between the ages of 20 and 30. It is calculated by multiplying your actual finish time by your age factor.

For example, if you finished a marathon in 4:30:00 and you are a 60-year-old male (meaning your age factor is 0.8183), to calculate your age-graded result, you would multiply 4:30:00 by 0.8183. This equates to 03:40:56.

Age-Graded Score

From this, we can calculate the age-graded running score. The age-graded score is your age-graded time as a percentage of the world record time. This functions as a method of comparison, whereby anyone can compare with anyone else of another age or gender.

For example, a 50-year-old could run a 5k slower than a 20-year-old, but if after calculating both runners’ age-graded scores we found that the 50-year-old had a higher age-graded percentage, then this would suggest that relative to their age, the 50-year-old actually performed better than the 20-year-old.

Ever wanted to compare your running performance to your dad, or even your grandma? Well, now you can.

A man running on a track

Race Time Predictions

The age-graded race time predictions are the finishing times of equal age-grade scores for other distances.

For example, if a 40-year-old female ran 4 miles in 30 minutes, this would equate to an age-graded score of 58%, signifying that they ran the distance 58% as fast as the world record time for said distance.

To calculate their predicted time for the half marathon, firstly, the calculator divides the world record for the half marathon distance by the runner’s age factor to get an age and gender-adjusted record time, then, the calculator divides this by the runner’s age-graded score to adjust the world record based on the runner’s ability.

It should be noted that the calculator tends to underpredict race times for longer distances, meaning that predictions for longer-than-half-marathon distances may be faster than how fast an individual would actually run the race.

Age Grade Formulas Used

Age Graded Result: finish time * age factor

Age Graded Score: (world record time / (age-graded result)) * 100

Predicted Time: world record time for desired prediction distance / age factor / (age-graded score for previous race / 100)