Training Calculator
Calculate training zones, find interval targets, and understand the relationship between intensity, lactate, and duration.
Your values
Highest power you can sustain for ~1 hour. Test: 4×12 min average × 0.95.
Don't know your FTP? Find it with a test ↓Test: warm up 15 min, then ride 30 min at the hardest steady pace you can sustain. LTHR ≈ average HR of the last 20 min.
↓ Download the LTHR test for Zwift (.zwo)Only used in the VO2max estimate (resting heart rate method).
Showing example values (FTP 250 W, 75 kg, max HR 185). Enter your own values above.
Rather set FTP slightly too low than too high: zones that are a little low still train in the right range. Read more about FTP, threshold heart rate and critical power →
Enter your intervals — duration, power, and rest for each effort. Choose a standard format or enter custom values. The calculator estimates FTP and training zones.
Import the file as a custom workout in Zwift. The test efforts are free ride, so you set the effort yourself.
My zones
Example values with FTP 250 W. Enter your own values above.
| Zone | Power | Heart rate |
|---|---|---|
Zone 1 — Recovery → Recovery | < 138 W | — |
Zone 2 — Endurance → Zone 2 continuous (65 min)→ Zone 2 long (65 min) | 138–200 W | — |
Zone 3 — Hard aerobic → Sweet spot: 3 x 15 min at 88-90% FTP | 200–238 W | — |
Zone 4 — Threshold → Threshold: 3 x 15 min at 95-97% FTP | 238–263 W | — |
Zone 5 — VO2max → VO2max: 5 x 5 min at 115% FTP | 263–300 W | — |
Zone 6 — Anaerobic | > 300 W | — |
Power is the primary tool; heart-rate ranges are guidance, as % of threshold heart rate. The links show example sessions from the session library, calculated with the FTP you entered.
Power Zones
| Zone | Power | % FTP |
|---|---|---|
Zone 1 — Recovery → Recovery | < 138 W | < 55% |
Zone 2 — Endurance → Zone 2 continuous (65 min)→ Zone 2 long (65 min) | 138–200 W | 55–80% |
Zone 3 — Hard aerobic → Sweet spot: 3 x 15 min at 88-90% FTP | 200–238 W | 80–95% |
Zone 4 — Threshold → Threshold: 3 x 15 min at 95-97% FTP | 238–263 W | 95–105% |
Zone 5 — VO2max → VO2max: 5 x 5 min at 115% FTP | 263–300 W | 105–120% |
Zone 6 — Anaerobic | 300–375 W | 120–150% |
Read more about the zones in the article Training zones and physiology →
Power-Duration Model
What can you hold, and for how long? Typical values relative to FTP.
| Duration | % FTP | Power |
|---|---|---|
| 1 min | 150% | 375 W |
| 2 min | 132% | 330 W |
| 5 min | 117% | 293 W |
| 10 min | 107% | 268 W |
| 20 min | 105% | 263 W |
| 60 min | 100% | 250 W |
| 3 h | 77% | 193 W |
| 5 h | 68% | 170 W |
Above threshold, it's a countdown — the higher the power, the shorter the duration. Below threshold, you can sustain for hours. The curve passes through the typical values in the table. Above threshold, the countdown is described by the critical power model: P(t) = CP + W'/t, where CP (critical power) is the boundary between work the body can sustain in a steady state and work that drains a limited reserve, W′.
Critical power model: Morton (2006), Eur J Appl Physiol 96(4):339–354. Power profile values: Pinot & Grappe (2011), Int J Sports Med 32(11):839–844. CP and FTP are not the same: CP was on average 7 W above FTP, with large individual differences (Karsten et al. 2020, Front Physiol 11:613151).
Heart Rate Zones
ZoneDeux zones are defined on power. If you train by heart rate, these ranges give guideline heart rates as a share of your threshold heart rate (LTHR).
Enter your threshold heart rate to see the zones in bpm. Go to threshold heart rate ↑
| Zone | Heart rate | % LTHR | |
|---|---|---|---|
| Zone 1 — Recovery | — | < 68 % | |
| Zone 2 — Endurance | — | 69–83 % | |
| Zone 3 — Hard aerobic | — | 84–94 % | |
| Zone 4 — Threshold | — | 95–105 % | |
| Zone 5 — VO2max | — | > 105 % | |
| Zone 6 — Anaerobic | No heart-rate guidance — heart rate lags effort by 1–3 minutes and does not reach its true level in short, maximal efforts. | ||
Guideline heart-rate ranges as % of LTHR, the same values as in the ZoneDeux zone table and training programs. Power is the primary tool; heart rate is a check. Read heart rate towards the end of intervals.
Read more about the zones in the article Training zones and physiology →
Lactate Model
How blood lactate responds to intensity and duration — and why 'lactate zones' above threshold don't make sense.
Lactate vs. intensity
Lactate vs. time above threshold
At threshold (100% FTP), lactate stabilizes. Above threshold, it rises continuously — the higher the intensity, the faster.
Above threshold, lactate rises continuously over time. A reading of 6 mmol/L could mean minute 15 at 105% FTP or minute 2 at 120% FTP — the same number, completely different physiological states. That's why it's more precise to talk about duration and power than lactate zones above threshold.
| Training concept | Lactate | % FTP | Power |
|---|---|---|---|
| Zone 2 — Endurance | 1.0–2.0 mmol/L | 55–80% | 138–200 W |
| Zone 3 — Hard aerobic | 2.0–4.0 mmol/L | 80–95% | 200–238 W |
| Zone 4 — Threshold (MLSS) | 3.5–5.5 mmol/L | 95–110% | 238–275 W |
| Zone 5 — VO2max (rising) | > 5 ↑ mmol/L | 110–120% | 275–300 W |
Lactate curve: exponential model based on Faude et al. (2009), Sports Medicine 39(6):469–490. Lactate accumulation above threshold: Jones et al. (2008), Am J Physiol 294(2):R585–R593. MLSS definition: Heck et al. (1985), Int J Sports Med 6(3):117–130. Optimal zone 2 (1.5–1.8 mmol/L): San Millán & Brooks (2018), Sports Medicine 48(2):467–479.
How Do You Compare?
Compare your FTP/kg with Coggan's power profile table.
Your FTP: 250 W / 75 kg = 3.33 W/kg
Male (W/kg)
| Level | 5 s | 1 min | 5 min | FTP |
|---|---|---|---|---|
| World Class | 23.3 | 10.8 | 6.93 | 5.82 |
| Exceptional | 21.5 | 10.1 | 6.31 | 5.29 |
| Excellent (Cat I) | 19.7 | 9.4 | 5.69 | 4.76 |
| Very Good (Cat II) | 17.9 | 8.7 | 5.07 | 4.22 |
| Good (Cat III) | 16.2 | 8.0 | 4.45 | 3.69 |
| Moderate (Cat IV)← you | 14.4 | 7.3 | 3.83 | 3.16 |
| Fair (Cat V) | 12.6 | 6.6 | 3.21 | 2.62 |
| Untrained | 10.8 | 5.9 | 2.59 | 2.09 |
Female (W/kg)
| Level | 5 s | 1 min | 5 min | FTP |
|---|---|---|---|---|
| World Class | 18.2 | 8.8 | 5.69 | 4.76 |
| Exceptional | 16.7 | 8.2 | 5.18 | 4.33 |
| Excellent (Cat I) | 15.3 | 7.6 | 4.67 | 3.90 |
| Very Good (Cat II)← you | 13.9 | 7.0 | 4.16 | 3.46 |
| Good (Cat III) | 12.5 | 6.4 | 3.65 | 3.02 |
| Moderate (Cat IV) | 11.1 | 5.9 | 3.14 | 2.59 |
| Fair (Cat V) | 9.7 | 5.3 | 2.63 | 2.15 |
| Untrained | 8.3 | 4.8 | 2.12 | 1.71 |
The women’s table is an estimate (about 85% of the men’s values), not Coggan’s published table for women. Category limits are approximate: halfway between the values of two neighbouring categories.
Modern context: Coggan's table vs. today's elite
Coggan's table was published around 2010 and has not been updated. Current Grand Tour riders exceed its top values. Pogačar and Vingegaard produce 6.8–7.0 W/kg over 30–40 minutes after hours of racing — their rested FTP is likely well above the table's 'World Class' ceiling of 6.04 W/kg.
| Rider | Duration | W/kg | Event |
|---|---|---|---|
| Pogačar | 40 min | ~7.0 | Plateau de Beille, TdF 2024 |
| Vingegaard | 13.5 min | ~7.5 | Stage 16 TT, TdF 2023 |
| Van der Poel | 3.3 min | 6.85 | Koppenberg, Ronde 2022 |
| Evenepoel | ~30 min | ~6.7 | Key climbs, TdF 2024 |
Table: Coggan & Allen (2010), 'Training and Racing with a Power Meter'. Modern data: Portoleau / chronoswatts.com (TdF 2024 analyses), welovecycling.com, Cyclingnews.
VO2max Estimator
Estimate your maximal oxygen uptake from various test methods. Field estimates have ±5–10% error margin compared to lab testing.