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Race Taper Calculator

Plan your weekly mileage reduction in the final weeks before a race using standard taper percentages.

Result

Week 1 of Taper
32 mi
Week 2 of Taper
26 mi
Week 3 of Taper
16 mi

Race week mileage typically drops the most - intensity (some faster efforts) is usually maintained even as total volume falls, so the legs stay sharp while fatigue clears.

Taper WeekTarget Mileage% of Peak
Week 132 mi80%
Week 226 mi65%
Week 316 mi40%

About the Taper Calculator

The Race Taper Calculator turns a runner's current weekly mileage into a week-by-week mileage target for the final one to three weeks before a race. Tapering, the practice of deliberately reducing training volume before a race, is a well-established part of endurance race preparation, and this tool applies standard taper percentages to a runner's own peak mileage. It removes the guesswork of deciding how much to cut back and when.

How It Works

Enter your current weekly mileage and choose a taper length of one, two, or three weeks. The calculator applies a fixed set of percentages to your mileage depending on the length chosen and returns a target mileage for each remaining week, along with what percentage of peak volume that represents. A three-week taper reduces volume more gradually than a one-week taper, which cuts volume more sharply in a single step.

Target Weekly Mileage = Current Weekly Mileage x Taper Percentage, where the percentages are fixed by taper length: 1 week uses 50%; 2 weeks uses 75% then 50%; 3 weeks uses 80%, 65%, then 40% of peak mileage.

Formula & Methodology

To apply this by hand, take your peak weekly mileage and multiply it by the percentage assigned to each remaining week in the sequence you chose. For a 3-week taper starting from 40 miles per week, week one is 40 x 0.80, or 32 miles, week two is 40 x 0.65, or 26 miles, and race week is 40 x 0.40, or 16 miles. The percentage always applies to the original peak mileage entered, not to the previous week's already-reduced total.

Examples

40 Miles Per Week, 3-Week Taper

A runner peaking at 40 miles per week following the 3-week pattern targets 32 miles, then 26 miles, then 16 miles in race week.

50 Miles Per Week, 2-Week Taper

A runner peaking at 50 miles per week using a 2-week taper targets 37.5 miles in the first week and 25 miles in race week.

Advantages

  • Applies commonly used taper percentages automatically instead of requiring a runner to calculate reduced mileage by hand each week.
  • Lets a runner compare how a 1-week, 2-week, or 3-week taper changes their weekly targets before committing to a plan.
  • Presents results in both a mileage table and percentage-of-peak format, making the reduction easy to visualize at a glance.

Common Mistakes

  • Cutting mileage without maintaining any race-pace intensity, which can leave the legs feeling flat and sluggish rather than sharp on race day.
  • Starting the taper too early or too late relative to the chosen taper length, which can undertrain or overtrain the final buildup.
  • Treating the percentage reduction as a one-size-fits-all rule regardless of race distance, when marathon tapers are typically approached differently than tapers for shorter races.

Edge Cases to Watch For

  • If a taper length is entered that does not match one of the three preset options, the calculator defaults to the 3-week pattern.
  • The percentages are fixed presets and do not adjust for injury history, race distance, or how much of a training block was actually completed, so they represent a general starting point rather than an individualized plan.
  • The calculator reduces total mileage only, on the assumption that some faster, race-pace effort is still included within that lower volume rather than being removed as well.

Common Use Cases

  • Marathon and half-marathon runners planning their final weeks of training before race day.
  • Coaches building standardized taper templates for athletes at different peak mileage levels.
  • Runners comparing a shorter, sharper taper against a longer, more gradual one before deciding which to follow.
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

Why reduce volume instead of just resting completely?

Cutting mileage while keeping some race-pace intensity lets your body clear accumulated fatigue and top off glycogen stores without losing fitness - research on tapering generally shows reductions of 40-60% in total volume over 1-3 weeks preserve fitness better than complete rest, which can lead to a feeling of sluggishness on race day.

Related calculators

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Conclusion

Tapering trades training volume for freshness, and getting that trade-off roughly right can meaningfully affect how a runner feels on race day. The Race Taper Calculator applies standard percentage reductions to a runner's own numbers so the mileage targets are concrete rather than left to guesswork.