Training load calculator
Power load calculator
Enter your workout data below to calculate your training stress score (TSS) for this session.
TSS (Training Stress Score) captures how hard a session was by combining how long you went and how hard you pushed, relative to your threshold power.
Load = (Duration × NP × IF × 100) / FTP
- Duration: workout time in hours
- NP: Normalized Power
- IF (Intensity Factor): NP / FTP
- FTP: Functional Threshold Power
By definition, one hour all-out at your FTP equals 100 TSS, so everything else scales from there.
Shape Calendar
Plan workouts by TSS, not by guesswork.
Describe a session in plain English, see the predicted TSS before you ride, and sync it to your Garmin or Apple Watch.