FTP cycling power calculator

FTP — the cyclist's functional threshold power

FTP is the highest average power you can sustain for ~1 hour. It's the single most important number in cycling training because every interval prescription, every zone, every TSS calculation is anchored to it.

Why 20 min × 0.95 (and not 60 min)

A true 60-minute all-out test is brutally hard, mentally and physically. Most riders can't pace it accurately. The 20-minute test is shorter, easier to pace, and the 0.95 multiplier accounts for the fact that you can hold ~5% more power for 20 minutes than for 60.

Alternatives: 8-minute test × 0.90, or ramp test (less accurate but indoor-trainer friendly).

Power-to-weight (W/kg) — the climbing currency

Pure power matters on flat. Power-to-weight matters on hills. The Coggan power profile chart classifies riders:

• <2.5 W/kg: untrained / casual
• 2.5-3.5: regular cyclist, recreational
• 3.5-4.5: trained amateur
• 4.5-5.5: Cat 2-3 racer / elite amateur
• 5.5+: Cat 1 / pro

Pro Tour climbers ride ~6.0-6.5 W/kg sustained on a 30-minute climb.

The seven power zones (Coggan)

The same Z1-Z5 framework as HR, plus Z6 (anaerobic) and Z7 (neuromuscular sprints). Power has the advantage over HR of being immediate — when you push the pedals harder, watts respond instantly, while HR has 30-90 second lag.