FTP Calculator
Functional threshold power from a field test: FTP, W/kg and power zones.
Average power of a 20-minute all-out effort Γ 0.95.
What FTP is and how it's calculated
FTP (Functional Threshold Power) is the highest power you can sustain for about an hour. It's the anchor of intensity in cycling and triathlon: power zones, TSS and interval plans are all built from it. The calculator takes your field test result, applies the protocol's proven factor and builds all 7 Coggan zones.
Which test to choose
The 20-minute test is the gold standard: after a warm-up, ride 20 minutes at the steadiest maximal power you can, FTP = 95% of the average. The ramp test is mentally easier: power rises in steps until failure, FTP β 75% of your best 1-minute power. The 8-minute test is shorter but demands aggressive pacing: FTP = 90% of the average. The hour test is the most accurate and the hardest β its average power is your FTP.
Frequently asked questions
How often should I retest FTP?
Every 6β8 weeks or after a significant training block. A stale FTP distorts zones and TSS: too low makes intervals easy, too high makes them impossible.
What is a good W/kg?
Recreational riders typically hold 2.5β3.5 W/kg at FTP, strong amateurs 4+, professionals 5.5β6.5 W/kg. W/kg matters most on climbs; absolute watts rule flat courses.
Why does the ramp test give a different result than the 20-minute test?
The ramp test leans more on anaerobic ability: it tends to overestimate FTP for punchy riders and underestimate it for diesels. Pick one protocol and repeat it β the trend matters more than absolute agreement.