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Race Time Predictor
Estimate equivalent 5K, 10K, half-marathon and marathon performances.
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Use a recent race result to explore equivalent performances and get a clearer picture of your current running fitness.
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Race Time Predictor
Enter a recent race result to estimate your equivalent performance at other distances.
Predictions update as you enter a valid time. Submitting checks that your input is valid.
Your estimated performances
Your race equivalents
5K
23:35
Pace / km 4:43
Pace / mile 7:35
10K
Your result49:10
Pace / km 4:55
Pace / mile 7:55
Half marathon
1:48:29
Pace / km 5:09
Pace / mile 8:17
Marathon
3:46:11
Pace / km 5:22
Pace / mile 8:38
Remember: these are equivalent-performance estimates, not guarantees. Longer races require endurance and appropriate preparation; your actual result will depend on training, conditions and course profile.
The RunBoxy toolkit
Useful tools. Clear answers.
We're building a focused collection of calculators for the questions runners actually ask.
02Available now
Running Pace Calculator
Convert a race time and distance into your average running pace.
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Run/Walk Calculator
Build up gradually from walking to your running goal. Create a flexible plan with manageable intervals and recovery days.
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Race Split Calculator
Plan your race pace with kilometre or mile splits. Choose an even, negative or positive split strategy and see your target checkpoint times.
Use calculator05Coming next
Training Pace Calculator
Find suggested training paces for easy runs, tempo sessions and intervals.
Explore RunBoxyBuilt around your running
Less guesswork. More purposeful running.
From choosing a target race pace to planning your next training block, RunBoxy aims to turn running data into practical decisions.
Try the race predictor