Calculator · Performance Lab
1RM Calculator
Estimate your one-rep max from a single set — with a full percent table for programming.
Ergebnis
- Estimated 1RM (Epley)
- 117.5kg
- 100 %
- 117.5kg
- 95 %
- 110kg
- 90 %
- 105kg
- 85 %
- 100kg
- 80 %
- 92.5kg
- 75 %
- 87.5kg
- 70 %
- 82.5kg
- 65 %
- 75kg
- 60 %
- 70kg
Brzycki for comparison: 112.5 kg.
≈ 1 reps
≈ 2 reps
≈ 3–4 reps
≈ 5–6 reps
≈ 7–8 reps
≈ 9–10 reps
≈ 11–12 reps
≈ 13–15 reps
≈ 16–20 reps
Explained
What this calculator does for you
Your 1RM (one-rep max) is the maximum weight you can move once with clean technique. It can be estimated reliably from any work set.
We use Epley as the default and show Brzycki for comparison. Both work well in the 1–10 rep range.
The real tool is the percent table: it translates your 1RM into concrete training weights for every intensity window.
Science
Scientific background
Epley: 1RM = weight × (1 + reps/30). Brzycki: 1RM = weight × 36 / (37 − reps).
Both models are validated for low rep counts; at high reps the spread widens because endurance and reps-in-reserve dominate.
True 1RM testing is standard in powerlifting but carries injury risk — only do it after targeted preparation.
Examples
Practical examples
5 reps at 100 kg
Epley ≈ 117 kg. Training weights: 85 % ≈ 99 kg, 75 % ≈ 87.5 kg, 65 % ≈ 75 kg.
3 reps at 140 kg
Epley ≈ 154 kg. Strength-programming window: 85–92 %.
Avoid these
Common mistakes
- 01Testing without warming up. Big injury risk.
- 02Extrapolating from 15+ reps. The estimate falls apart.
- 03Ego lifting: sloppy technique inflates the number — and costs you later.
- 04Ignoring the percent table and always training at the supposed 1RM.
Recommendations
Further recommendations
- 01Use the percent table to distribute volume, strength and peak intensity cleanly.
- 02Verify estimated 1RMs on lifts you actually test maximally (squat, bench, deadlift).
- 03Update the estimate after each training block — not every two weeks.
FAQ
Frequently asked questions
- How often should I re-estimate my 1RM?
- Every 4–8 weeks or after a training block. More often rarely helps.
- Epley or Brzycki?
- In the 1–10 rep range they're close. Epley tends to read slightly higher at higher reps.
- Should I test a true 1RM?
- Only if you've warmed up, technique is solid and you actually need it for competition. Otherwise estimates are safer.
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Deload Calculator
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Knowledge Hub
More on this in the Knowledge Hub
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