- Epley estimate
- 116.67 kg
- Brzycki estimate
- 112.5 kg
- Lombardi estimate
- 117.46 kg
How it works
Model disagreement is useful information
For 100 kg lifted five times, Epley gives about 116.7 kg while Brzycki gives 112.5 kg. The gap comes from different equations, so a decimal-rich prediction should not be mistaken for a tested maximum.
Comparing estimated lifting maximums
A one-repetition-maximum estimate uses a weight lifted for several repetitions to infer a single-repetition value under the displayed equation. The estimate is sensitive to the repetition count and how representative the set was. Use it as a comparison of entered sets, not an instruction to attempt the predicted load. The calculation cannot assess technique, fatigue, injury, or readiness to lift.
Estimated maximum: formula and assumptions
Epley: 1RM ≈ weight × (1 + reps/30). Brzycki: 1RM ≈ 36 × weight / (37−reps). Lombardi: 1RM ≈ weight×repetitions^0.1.
These equations are estimates. Technique, fatigue, exercise selection, and training history affect the result.
Equations become less reliable at higher repetition counts. Lombardi is shown for up to 10 repetitions; it is a historical predictive equation, not a measured maximum.
Worked example
Using the Estimated maximum example:
- Weight lifted (kg)
- 100
- Repetitions
- 5
- Weight unit
- Kilograms
Epley: 1RM ≈ weight × (1 + reps/30). Brzycki: 1RM ≈ 36 × weight / (37−reps). Lombardi: 1RM ≈ weight×repetitions^0.1.
Example result
Epley estimate: 116.67 kg
Brzycki estimate: 112.5 kg
Lombardi estimate: 117.46 kg
These are illustrative inputs. Change the values to explore a different scenario.
Formula references
- NSCA: strength and conditioning resources (opens in a new tab)
- Reynolds et al. (2006): comparison of 1RM prediction equations, Table 5 (opens in a new tab)
References explain the underlying methods; they do not imply endorsement or individual professional review of Finflo.
Common questions
Is the predicted one-rep maximum a weight I should attempt?
No. It is an estimate, not a safety assessment. Technique, fatigue, training experience and the exercise affect actual capacity.
Why do estimates become less reliable with more repetitions?
Predictive equations extrapolate from repetitions to a maximum. Their assumptions become less dependable as the repetition count increases.
Prepared by Finflo. See our methodology and editorial policy. Read the relevant professional-advice limitations.