Four tools in one: a pace and speed calculator, a race-time predictor, a distance converter, and a ranking scale that places your time on a line from beginner to world class, adjusted for age and sex. Everything runs in your browser; nothing you type is sent anywhere.
What pace am I running?
Enter how far you went and how long it took.
Predict your other distances
Enter one recent race; it estimates the others using Riegel's formula. Predictions assume you're trained for each distance.
Metres · Kilometres · Miles · Yards · Feet
Handy for track sessions, treadmill settings and yard-marked courses.
Beginner to world class
Pick your distance, sex and age, enter your time, and see where you land. The scale is age-adjusted, so it compares you fairly across the years.
What the ranking actually means
The levels are approximate benchmarks drawn from how the running population spreads out, from people who've just started to the very top of the sport. Beginner is roughly where a healthy adult lands in their first weeks of training; Intermediate is a committed recreational runner who trains regularly; Advanced is a strong club runner; Elite is competitive at a regional or national level; and World class sits near the records. Most people who run consistently for a year or two settle somewhere in the Novice-to-Advanced range — and moving up a band is the work of months, not days. Treat it as a motivating snapshot, not a verdict.
Why it adjusts for age and sex
Raw finish times aren't a fair comparison across very different runners, so the scale does two things. It uses separate benchmarks for men and women, reflecting real physiological differences in endurance performance. And it age-adjusts your time using a simplified version of the age-grading curves that masters athletics uses: performance peaks in the late twenties to thirties and gradually declines after, so an older runner's time is credited accordingly. A 55-year-old and a 25-year-old running the same 10K won't sit in the same place on a raw scale — but age-graded, they might be the same level.
How the race predictor works
The predictor uses Riegel's formula, which scales your time by the ratio of distances raised to a fatigue exponent. It's remarkably good between nearby distances — a 5K predicting a 10K, say. It gets optimistic for the marathon, because finishing 42 km well depends on endurance base and fuelling that a short race simply doesn't test. If you've never run beyond 10K, treat the predicted marathon as a best case that assumes the training is in the bank.
How accurate are the ranking benchmarks?
Why is the age adjustment only approximate?
Which distances does the predictor cover?
This calculator is provided for general interest and motivation. Rankings use approximate population benchmarks and a simplified age-grading curve; predictions use a standard formula and assume appropriate training. None of it is coaching or medical advice. Build mileage sensibly and consult a professional before starting or changing a training programme.