How it works
Fill in the 2 fields above and 1RM Percentage Calculator calculates the result instantly, recalculating as you change any value. The math runs locally in your browser — nothing is sent to a server.
Examples
- One-rep max 100 kg, Percentage 80 % → Training weight: 80 kg
Frequently asked questions
How do I use the 1RM Percentage Calculator?
Enter your values in the 2 input fields and the result is calculated automatically as you type. Change any value to see the numbers update instantly.
Is my data private?
Yes. The 1RM Percentage Calculator runs entirely in your browser. Nothing you enter is uploaded, saved to a server, or shared — it never leaves your device.
Is the 1RM Percentage Calculator free?
Yes, it is completely free with no sign-up, no limits and no watermarks. Like every tool on health & fitness and the rest of the platform, you can use it as often as you like.
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