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Overhead Press 1RM calculator
This overhead press 1RM calculator turns a set you have already completed into an estimated max and working weights.
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Enter a strict press, with no leg drive, from shoulders to lockout. The weights are small, so expect working weights to fall between the plates you have — round to the next available load.
A set you have already done
Estimated one-repetition maximum
53.3 kg
53.3 kg
From 40 kg × 8 reps at 2 RIR (Epley)
| Reps | 0 RIR | 1 RIR | 2 RIR | 3 RIR |
|---|---|---|---|---|
| 3 | 48.5 kg | 47 kg | 45.7 kg | 44.4 kg |
| 5 | 45.7 kg | 44.4 kg | 43.2 kg | 42.1 kg |
| 8 | 42.1 kg | 41 kg | 40 kg | 39 kg |
| 10 | 40 kg | 39 kg | 38.1 kg | — |
| 12 | 38.1 kg | — | — | — |
A warm-up ramp to 40 kg (8 reps, 2 in reserve)
| Set | Weight | Each side |
|---|---|---|
| 1 | 20 kg | bar only |
| 2 | 27.5 kg | 1 × 2.5 + 1 × 1.25 |
| 3 | 32.5 kg | 1 × 5 + 1 × 1.25 |
| Working | 40 kg | 1 × 10 |
Roughly 40, 55, 70 and 85 per cent of the working weight, for a few easy reps each, then the working set. A general guide, not a prescription — add or drop steps to suit the lift and how you feel.
Uses the Epley equation, counting reps in reserve as reps you could have done. It is only an estimate from a set you have already completed, not a test of your maximum; a dash means the combination is outside the range the equation is reliable over. Round to the nearest weight your equipment allows.
Got your overhead press estimate? Try the next lift.
Romanian Deadlift 1RM calculator →Something feels off in the overhead press itself? Get one technique cue for your next overhead press set.
Wondering whether this lift is keeping up with the others? Compare your lifts with the lift ratio calculator, or score your total with the DOTS and Wilks calculator.
Picking effort rather than weight? Use the RPE and RIR calculator.
Got your working weight? Work out your warm-up sets and plates. See your lifts as a multiple of your bodyweight, or score a competition total with IPF GL points.
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How the calculation works
The Epley estimate is load × (1 + effective repetitions ÷ 30). Effective repetitions are completed reps plus reps in reserve: the extra reps you believe you could have completed with the same technique. A single rep with none in reserve is returned as the entered load. The working-weight table rearranges the same equation for each target.
Worked example
A completed set of 100 kg for 8 reps with 2 reps in reserve gives 10 effective repetitions. The calculator returns an estimated one-rep max of 133.3 kg. This is a calculation example, not a recommendation to attempt that weight.
What the result cannot tell you
Repetitions plus reps in reserve must be 12 or fewer. An estimate is not a tested maximum: technique, fatigue and the accuracy of your RIR estimate affect it. Keep comparisons to the same exercise, equipment and range of motion, and round working weights to what you can load.
Common questions
Do I need to test my maximum?
No. Enter a set you have already completed. The result estimates a maximum without requiring a maximal attempt.
Why is there a dash in the table?
That target's reps plus reps in reserve exceed the calculator's supported range. The tool leaves it blank rather than showing an unsupported estimate.
What does 2 RIR mean?
You believe you could have completed about two more full reps with the same technique. It is a subjective estimate, not a measured fact.
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Educational information for adults aged 18 and over. It does not diagnose, treat or manage any medical condition. If you have a health condition, or symptoms that worry you, speak to your doctor or a health professional.