What is your one-rep max if you lift 80 kg for 5 reps?
Estimate your 1RM — the most weight you could lift once — without having to risk actually testing it. Enter the weight and reps of a set you completed and we calculate your 1RM with the three most widely used formulas, plus a table of training loads by percentage.
Estimated using the Epley, Brzycki and Lombardi formulas. Most reliable with sets of 1-5 reps. Never test a true 1RM without warming up and, ideally, a spotter.
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How is 1RM calculated?
Your one-rep max is the heaviest weight you could lift once with good technique. You do not have to test it to know it: with the weight you lifted and the number of reps you managed, a handful of validated equations estimate it well. We show three — Epley, Brzycki and Lombardi — because they disagree slightly and the spread between them is the honest margin of error. All three are most accurate below about 10 reps; past that the estimate drifts, because endurance starts to matter more than maximum strength. Under the result you get the percentage table, which is what you actually program your training from.
Your 1RM by weight and reps
Find the reps you did in the row and the weight you moved in the column: the cell is your estimated one-rep max. The formulas lose accuracy above 10-12 reps, which is why the table and the calculator stop at 12.
| Reps | With 40 kg | With 60 kg | With 80 kg | With 100 kg |
|---|---|---|---|---|
| 2 reps | 42 kg | 63.5 kg | 84.5 kg | 105.5 kg |
| 3 reps | 43.5 kg | 65.5 kg | 87.5 kg | 109 kg |
| 4 reps | 45 kg | 67.5 kg | 90 kg | 112.5 kg |
| 5 reps | 46 kg | 69.5 kg | 92.5 kg | 115.5 kg |
| 6 reps | 47.5 kg | 71 kg | 95 kg | 118.5 kg |
| 8 reps | 50 kg | 75 kg | 99.5 kg | 124.5 kg |
| 10 reps | 52.5 kg | 78.5 kg | 104.5 kg | 131 kg |
| 12 reps | 55 kg | 82.5 kg | 110 kg | 137.5 kg |
Source: the same function as the calculator, the average of the Epley, Brzycki and Lombardi formulas, rounded to 0.5 kg. It is an estimate, not a real one-rep attempt. These are reference ranges for healthy adults, not a diagnosis or individual advice.
FAQ
What is my 1RM if I lift 80 kg for 5 reps?
About 92.5 kg, using the average of the Epley, Brzycki and Lombardi formulas. With 60 kg for 5 reps it would be 69.5 kg, and with 100 kg for 5, 115.5 kg. The more reps, the further the estimate drifts from reality, which is why the calculator stops at 12.
What is my bench press max if I do 60 kg for 8 reps?
The estimate comes out at 75 kg. With 60 kg for 10 reps it would be 78.5 kg, and for 3, 65.5 kg. The same works for squat and deadlift, as long as the reps are done with good form and close to failure.
What is 1RM?
The maximum weight you can lift for a single repetition with correct technique. It is the reference strength programmes are written against: most sets are prescribed as a percentage of it rather than as an absolute weight, so it travels with you as you get stronger.
Do I have to attempt a real 1RM to know it?
No, and for most people it is not worth it. A true max attempt is technically demanding, needs a spotter and carries real injury risk. Estimating from a set of 3-8 reps taken close to failure gets you within a few percent, which is plenty for programming.
What percentage do I use for muscle or for strength?
Broadly: strength lives at 85-95% for 1-5 reps, hypertrophy at 65-80% for 6-12, and muscular endurance below 65%. These bands overlap far more than most programmes suggest — total hard sets matter more than landing on an exact percentage.
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