Cycling FTP Calculator

Estimate your Functional Threshold Power (FTP) from a 20-minute test, ramp test, or 8-minute test.
Calculate your power training zones.

FTP & Training Zones

FTP (Functional Threshold Power) is the cornerstone metric of structured cycling training. It represents the highest average power output — measured in watts — that a rider can sustain for approximately one hour. All training zones, workout targets, and performance benchmarks are calculated as percentages of FTP, making it the single most important number in a cyclist’s training file.

FTP estimation formulas by test type:

FTP (20-min test) = Average Power over 20 minutes × 0.95

FTP (8-min test) = Average Power over 8 minutes × 0.90

FTP (Ramp test) = Peak 1-minute power of last completed step × 0.75

Power-to-Weight Ratio:

W/kg = FTP (watts) / Body Weight (kg)

Variable definitions:

  • FTP: Functional Threshold Power; the power level at lactate threshold (where lactate production equals clearance)
  • 0.95 factor: the 20-min test produces power slightly above true 1-hour threshold; the 5% reduction normalizes it
  • W/kg: watts per kilogram; the truest measure of climbing ability and comparative performance across body sizes
  • Training Zones: power ranges defined as percentages of FTP, each targeting a specific physiological adaptation

Worked example: A 75 kg cyclist averages 285 watts over a 20-minute FTP test. FTP = 285 × 0.95 = 270.75 watts → 271 watts W/kg = 271 / 75 = 3.61 W/kg — competitive recreational level

Training zone targets based on FTP:

Zone Name % of FTP Power (271W FTP)
Z1 Active Recovery <55% <149W
Z2 Endurance 56–75% 152–203W
Z3 Tempo 76–90% 206–244W
Z4 Threshold 91–105% 247–285W
Z5 VO2 Max 106–120% 287–325W
Z6 Anaerobic 121–150% 328–407W

W/kg performance benchmarks:

W/kg Rider Category
1.5–2.5 Beginner / untrained
2.5–3.5 Recreational / fitness rider
3.5–4.5 Competitive / Cat 3–4
4.5–5.5 Elite / Cat 1–2
5.5+ Professional road cyclist

Retesting frequency: FTP changes with training. Retest every 6–8 weeks during active training blocks. FTP typically improves 5–15% over a well-structured 12-week training plan for recreational riders. Tour de France winners average 6.0–6.5+ W/kg at threshold — a number most riders can only dream of.


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This calculator runs entirely in your browser, so the numbers you enter stay on your device. The math behind it is written by hand and tested against worked examples and standard references before the page goes live.

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