CYCLING CALCULATORS
Every number you need, worked out from the data your trainer already gives you.
WHAT TO WORK OUT FIRST
- FTP. Everything else depends on it. Do a ramp or 20-minute test, then use the first calculator below.
- Power zones. Turn that FTP into the watt bands you will actually ride to.
- Watts per kilo. How you compare, and how you will climb.
- Heart rate zones. Useful for keeping easy rides easy and interpreting how hard a session really was.
- Calories. From power, which is the only estimate worth trusting.
FTP CALCULATOR
FTP = 95% of your 20-minute average power. At 2.92 W/kg you sit in the Moderate band — rides often, fit sportive finisher. A regularly training rider of 38 is typically around 3.00 W/kg, so you are 0.08 W/kg below it.
POWER ZONE CALCULATOR
| Zone | Name | % FTP | Watts | What it's for |
|---|---|---|---|---|
| Z1 | Active Recovery | 0-55% | 0-127W | Flushing the legs between hard days |
| Z2 | Endurance | 56-75% | 129-173W | Aerobic base, fat oxidation, capillary growth |
| Z3 | Tempo | 76-90% | 175-207W | Muscular endurance when time is short |
| Z4 | Threshold | 91-105% | 209-242W | Raising FTP itself |
| Z5 | VO2 Max | 106-120% | 244-276W | Top-end aerobic power |
| Z6 | Anaerobic | 121-150% | 278-345W | Attacks, short climbs, race winning moves |
| Z7 | Neuromuscular | 151%+ | 347W + | Sprint power and leg speed |
WATTS PER KILO CALCULATOR
Another 3W at the same weight would move you into "Good". Losing 2kg at your current FTP would put you at 3.15 W/kg.
HEART RATE ZONE CALCULATOR
| Zone | Name | % max | BPM | Feel |
|---|---|---|---|---|
| Z1 | Recovery | 50-60% | 93-111 | Easy spin, conversational, active recovery. |
| Z2 | Endurance | 60-70% | 111-130 | All-day pace. Builds aerobic base. |
| Z3 | Tempo | 70-80% | 130-148 | Sustained effort, slightly laboured breathing. |
| Z4 | Threshold | 80-90% | 148-167 | Hard. Sustainable ~30–60 min. FTP territory. |
| Z5 | VO2 / Red | 90-120% | 167-185 | Red line. Short, hurts, cannot hold long. |
CALORIES BURNED CALCULATOR
A cyclist converts roughly 20-25% of the energy they burn into forward power, and a kilojoule is about a quarter of a calorie. Those two numbers very nearly cancel out, which is why kilojoules of work and kilocalories burned come out close to 1:1. That makes power-based calorie estimates far more trustworthy than the guesswork you get from speed or heart rate alone.
THE GUIDES BEHIND THE NUMBERS
FAQ
Are these calculators accurate?
Do you store my numbers?
Why are calories estimated from power rather than speed?
KEEP READING
PUT IT INTO PRACTICE
LuftQuest is a free indoor cycling app: pair your power meter, pick a structured workout and let a very opinionated coach keep you honest.