Taper Schedule Calculator
Determine how much to reduce your weekly mileage during the weeks before a marathon or half marathon. Ideal for runners finalizing their race-week training plan.
About this calculator
Tapering is the structured reduction of training volume in the weeks before a race to allow your body to recover and peak on race day. This calculator uses your peak weekly mileage and reduces it progressively based on taper style and duration. The core formula is: weeklyMileage = peakMileage × (1 − reductionRate × (weeksToTaper / totalTaperWeeks)) × experienceFactor. The reduction rate varies by style: aggressive tapering cuts up to 50%, moderate cuts 30%, and conservative cuts 20%. Marathon tapers typically span 3 weeks, while half marathons use 2 weeks. An experience multiplier adjusts the output for runners at different fitness levels, ensuring the schedule reflects realistic recovery needs.
How to use
Imagine a marathon runner with a peak weekly mileage of 50 miles, choosing a moderate taper over 3 weeks. Week 1 reduction: 50 × (1 − 0.3 × (1/3)) = 50 × 0.9 = 45 miles. Week 2: 50 × (1 − 0.3 × (2/3)) = 50 × 0.8 = 40 miles. Week 3 (race week): 50 × (1 − 0.3 × (3/3)) = 50 × 0.7 = 35 miles. If an experience factor of 1.0 is applied, the schedule stays as shown. The calculator produces these weekly targets automatically, removing guesswork from your pre-race plan.
Frequently asked questions
How many weeks before a marathon should I start tapering?
Most training plans recommend beginning your marathon taper 3 weeks before race day. During this period, weekly mileage drops progressively while intensity may remain moderate to maintain fitness sharpness. Cutting too early risks losing aerobic fitness, while tapering too late leaves accumulated fatigue in your legs on race day. For half marathons, a 2-week taper is generally sufficient.
What is the difference between aggressive and moderate taper styles for runners?
An aggressive taper reduces weekly mileage by up to 50% from peak, which benefits runners carrying high fatigue or those who respond strongly to rest. A moderate taper cuts approximately 30%, balancing recovery with fitness maintenance, and suits most recreational and intermediate runners. A conservative taper of around 20% works well for experienced runners who fear losing conditioning quickly. Your choice should reflect how your body historically responds to reduced training volume.
Why do I feel sluggish and tired during my marathon taper period?
Feeling sluggish during taper, often called 'taper madness,' is extremely common and does not indicate declining fitness. Your body is consolidating adaptations from months of training, replenishing glycogen stores, and repairing micro-muscle damage. Legs that feel heavy or restless are a normal neurological response to suddenly reduced volume. Trust the process — most runners report feeling noticeably fresher and more powerful on race morning after a proper taper.