TSS calculator for cycling
One hour exactly at threshold is 100 TSS. Start from a power, or from the repeats.
Worked example
Worked example: 64 TSS. Load. Intensity: 0.80. Duration: 1:00:00. Change the numbers and the result updates immediately.
How to use it
- Use normalized power if you have it. Average power makes the load an estimate.
- For intervals, choose Repeats: watts and minutes on, then watts and minutes off.
- One hour held exactly at threshold scores 100. Below is easier, above is harder.
Intensity is normalized power divided by FTP. TSS combines duration and intensity. If you enter the average instead of normalized power, the load is an estimate: it ignores changes of pace. With repeats, the calculator builds normalized power itself: a 30-second rolling average, then the fourth power, so a surge weighs more than an easy spin. Rest in between counts. Rest after the last repeat does not.
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