Estimate a one-repetition maximum from a completed weight and rep set across common formulas.
Change the inputs that matter to your decision. Optional assumptions stay collapsed until you need them.
Use a completed submaximal set. Do not test a true maximum without appropriate supervision and equipment.
Brzycki estimate from 100.0 kg × 5 reps.
| 100% · 1RM test | 112.5 kg1 reps |
|---|---|
| 95% · Max strength | 106.9 kg1–2 reps |
| 90% · Max strength | 101.3 kg2–4 reps |
| 85% · Strength | 95.6 kg4–6 reps |
| 80% · Strength | 90.0 kg5–8 reps |
| 75% · Power/strength | 84.4 kg6–10 reps |
| 70% · Power | 78.8 kg8–12 reps |
A one-rep-max formula is an estimate from submaximal performance. Warm up and use safety equipment for heavy lifting.
Practical notes about the inputs, assumptions, and result.
Brzycki is a common general-purpose starting point. Comparing the formula range can show how sensitive the estimate is to the method and rep count.
No. It estimates a maximum from a submaximal set. Heavy attempts require appropriate preparation, supervision, equipment, and judgment.
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