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Draft Benefit Calculator
Calculate energy savings from drafting behind other riders.
How We Calculate This
Drafting Physics
The lead rider creates a low-pressure wake behind them, so following riders meet less air. Aerodynamic drag reductions vary by position (Blocken et al. 2018): 2nd wheel ~27%, 3rd wheel ~30%, sheltered mid-pack ~35% or more. Drafting cuts the aero drag only — your rolling resistance and the effort to climb are unchanged. Wind direction and speed modify these values.
Speed at Same Power
Aerodynamic drag rises with the cube of speed, so a ~27% cut in aero drag lets you hold roughly a 10% higher speed for the same effort (e.g. 40 km/h solo becomes about 44 km/h on the wheel).
Frequently Asked Questions
Riding directly behind another cyclist at close range saves 25-35% of aerodynamic drag. The exact savings depend on gap distance, rider sizes, speed, and wind conditions. At 40 km/h, this can mean saving 50-80 watts.
Yes, significantly. At one bike length (1.5m), you get maximum benefit. At 2-3 bike lengths, savings drop to about 15-20%. Beyond 5 bike lengths, the draft effect is negligible.
A headwind increases the draft benefit because more of the wind is blocked by the lead rider. A crosswind reduces the benefit because the draft shadow shifts to the side. In echelon formation, riders offset to the sheltered side.
Drafting is legal in road races and criteriums but banned in most time trials and triathlons. In non-drafting events, riders must maintain a specified gap (typically 10-12 metres). Check event rules before racing.
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Last updated: June 2026
All calculations are estimates. Always verify results and consult a professional bike fitter where appropriate.