Running Calculator with adjustments for temperature and body weight, plus FIRST training paces

This calculator will generate training paces, race prediction, with adjustments for temperature, body weight and altitude. This calculator works by estimating your V̇O₂max and using that to predict your race times and training paces. To find out your V̇O₂max and associated paces, you will need the results of a recent race into the form below.

• You may have several race results that indicate different V̇O₂max values. If the races are all reasonably recent and reflect your current fitness level, use the best. If you've been injured or had a break from training since your last race, you should not use an old race result.
• This Calculator will also attempt to compensate for races run in hot conditions. This is based on the research documented at Impact of Heat on Marathon Performance and is an estimate only. If you enter your weight, the calculator will predict your race performances at different body weights, assuming the weight change is due to body fat only.
• This calculator no longer generates VDOT paces nor will it output the long runs for the Jack Daniels marathon plans. Jack Daniels requested the removal of this functionality.
• If you provide your power values, the calculator will display running power for each pace. It modifies the simple "1 watt per Kg per meter" approximation with an offset. I find that a weight 1.5Kg less than my real weight and an offset of 22w matches Stryd for me.

Distance 1500 Meters Mile 3K 2 Miles 5K 8K 5 Mile 10K 15K 10 Mile 20K Half Marathon 25K 30K Marathon
Time
Body Weight KgPoundsGiven body weight, we can estimate how weight changes will impact performance
Body Fat Given body weight and body fat %, we can improve our estimate of performance changes
Weight for Power (optional, Kg.) Power Offset To match Stryd, try 1.5Kg less than real weight and 22w offset
Heat Index (optional) FahrenheitCentigrade
Max Weekly Distance(optional, miles/Km)
Show Unusual Distances (8K, etc.)
Show Longer Distances (Beyond 50K)
Show paces in min/Km rather than min/mile, plus over values in metric units.