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Enter a one rep max and get every training percentage instantly, rounded to weights you can actually load on a bar.
Never recalculate again
Every time you set a PR, the app automatically recalculates all your training weights. No spreadsheet needed.
Training at specific percentages of your 1RM is the foundation of scientific strength programming. Different percentages target different adaptations - heavy percentages (85–95%) build maximal strength, moderate percentages (70–85%) build size and strength simultaneously, and lighter percentages (50–70%) develop technique and endurance.
5/3/1 by Jim Wendler is one of the most popular strength programs in the world. It rotates weekly intensity across three weeks (5s, 3s, 1s) with an AMRAP set on the last set to accumulate volume and push past your calculated percentages. The fourth week is a deload.
Retesting every 4–8 weeks is common for intermediate lifters. Beginners can progress more frequently (every 2–4 weeks). Using submaximal AMRAPs (as in 5/3/1) lets you estimate your 1RM without maxing out every training cycle.
Got your number. Now keep it.
The app saves every result and shows the trend, so the next calculation starts from something real.
A strength programme cannot prescribe absolute weights, because the same session has to work for a lifter squatting 80 kg and one squatting 200 kg. So it prescribes intensity as a share of your max, and you do the arithmetic:
working weight = 1RM × (percentage ÷ 100)
Worked example: your back squat max is 140 kg and the session calls for 5 sets of 3 at 80 %. That is 140 × 0.80 = 112 kg. With 1.25 kg plates available you would load 112.5 kg, because that is the nearest weight the bar can actually make.
| Percentage | 1RM 100 kg | 1RM 140 kg | 1RM 180 kg |
|---|---|---|---|
| 95 % | 95 kg | 133.0 kg | 171.0 kg |
| 90 % | 90 kg | 126.0 kg | 162.0 kg |
| 85 % | 85 kg | 119.0 kg | 153.0 kg |
| 80 % | 80 kg | 112.0 kg | 144.0 kg |
| 75 % | 75 kg | 105.0 kg | 135.0 kg |
| 70 % | 70 kg | 98.0 kg | 126.0 kg |
| 65 % | 65 kg | 91.0 kg | 117.0 kg |
| 60 % | 60 kg | 84.0 kg | 108.0 kg |
| 55 % | 55 kg | 77.0 kg | 99.0 kg |
| 50 % | 50 kg | 70.0 kg | 90.0 kg |
This is what percentages look like in practice: intensity climbs while volume falls, then you deload and test.
| Week | Intensity | Sets × reps | Purpose |
|---|---|---|---|
| Week 1 | 70 - 75 % | 5 × 5 | Volume, rebuild work capacity |
| Week 2 | 75 - 80 % | 5 × 4 | Volume with more load |
| Week 3 | 80 - 85 % | 5 × 3 | Intensity climbs, volume drops |
| Week 4 | 60 % | 3 × 5 | Deload |
| Week 5 | 85 - 90 % | 4 × 2 | Peak |
| Week 6 | 95 - 100 % | Singles | Test a new max |
Percentages produce numbers a barbell cannot make. 77 % of 143 kg is 110.11 kg. The rule most coaches use is to round to the nearest loadable increment, which is twice your smallest plate, and to round down rather than up on heavy days. Being 2 kg light on a top set costs you nothing. Being 2 kg heavy is how a planned triple turns into a grinding double.
This calculator gives you one number. The app remembers every number, charts your progress and tells you when you are due for a new PR.
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