One Rep Max Comparison
Estimate one-rep max with three common formulas.
Calculate one rep max comparison from clear inputs
One Rep Max Comparison gives a focused worksheet for health & fitness questions where a quick deterministic estimate is more useful than a spreadsheet. The one rep max comparison fields mirror the variables in its formula, and the output separates the main result from supporting values so you can sanity-check this calculation before reusing it.
100 for 5 reps gives an Epley estimate of 116.667 and Brzycki estimate of 112.5.
Keep the estimate private in your browser
For One Rep Max Comparison, every calculation runs in your browser with no upload, account, cookie, live lookup, or server-side storage. The one rep max comparison result is best treated as a planning number because the real-world constraints behind this estimate can change the answer. Adjust the one rep max comparison assumptions and confirm important decisions against the relevant source of truth for that exact situation.
Frequently Asked Questions
Which one-rep max formulas does it compare?
Epley: weight × (1 + reps ÷ 30). Brzycki: weight × 36 ÷ (37 − reps). Lombardi: weight × reps^0.1. 100 kg for 5 reps gives 116.7, 112.5, and 117.5.
Why do the formulas disagree?
Each was fitted to different lifters and rep ranges. They agree closely at 2 to 5 reps and drift apart as reps increase.
How many reps give the most reliable estimate?
Sets of 3 to 6 reps taken close to failure. Estimates from 10 or more reps are much less reliable, and Brzycki breaks down entirely near 37 reps.
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