How the eRM is calculated
The eRM (estimated repetition max) is the heaviest weight you are expected to make for the whole set as written: every part, its reps and the rounds. For one rep of one lift it is the same idea as an e1RM, an estimated one-rep max.
The one-rep level of each part
A snatch or a clean & jerk reads your own PR. Every other movement is a ratio of one of them. For the squats, presses, pulls and the overhead squat the ratio comes from a range model that moves with your strength and your age (enter your age to use it). For the hang and power variants it comes from measured ratios. For the rest it comes from coaching convention, and the result shows as a range. A clean reads the higher of your clean and your clean & jerk.
The rep factor
The share of your one-rep max you can lift for a set of that many reps. Rounds count as one continuous set: one rep for three rounds reads as a triple.
| Reps | Snatch, clean, jerk | Power and hang | Squat, deadlift, strict press | Pulls |
|---|---|---|---|---|
| 1 | 1.00 | 1.00 | 1.00 | 1.00 |
| 2 | 0.94 | 0.94 | 0.95 | 0.95 |
| 3 | 0.90 | 0.90 | 0.93 | 0.92 |
| 4 | 0.86 | 0.87 | 0.90 | 0.89 |
| 5 | 0.83 | 0.84 | 0.87 | 0.86 |
| 6 | 0.80 | 0.81 | 0.85 | 0.83 |
The complex factor
Chaining parts without putting the bar down costs a little more than the weakest part alone. The weakest part, at its own reps, sets the level; the factor covers the chain.
| Parts | Factor |
|---|---|
| 2 | 0.96 (one pull before the lift it rehearses: 0.98) |
| 3 | 0.93 |
| 4 | 0.90 |
| 5 | 0.88 |
A clean followed by a jerk, one of each, is the clean & jerk itself: no complex factor.
A worked example: snatch + 2 overhead squats
Take a 100 kg snatch and a 120 kg clean & jerk, no age given. The snatch part reads your PR: 100 kg at one rep. The overhead squat has no PR of its own, so its level is its ratio to your snatch, read at two reps (0.94). It is the weaker part, so it limits the set, and the two-part factor of 0.96 covers the chain. The result is 80–103 kg: a range, because the overhead squat's ratio is coaching convention rather than a measurement.
Compared with Epley, Brzycki and the percentage charts
Epley (1RM = weight × (1 + reps ÷ 30)) and Brzycki (1RM = weight × 36 ÷ (37 − reps)) were fitted to strength lifts. For a triple they give 91 % and 94 % of the one-rep max. The NSCA percentage table gives 93 %, which is what this calculator uses for squats, deadlifts and strict presses. The snatch and the clean & jerk lose more per extra rep, because speed and position fade before strength does, so a snatch triple reads at 90 %. Prilepin's chart answers a different question, how many reps to do at a given percentage, and is not a max formula.
Questions
What is eRM?
An estimated repetition max: the heaviest weight you are expected to make for a whole set as written. In the Nosto app every estimate is called eRM and drawn in orange, and "PR" only ever means a weight you have actually lifted.
How do I estimate my snatch max from a double or a triple?
Divide the weight by the rep factor: 0.94 for a double, 0.90 for a triple. An 85 kg double suggests a single near 90 kg. The Nosto app does this for you: a strong double or triple raises the single it implies.
How much should I snatch for a triple?
About 90 % of your snatch PR. Pick Snatch and 3 reps above to see it for your numbers.
Does it work for complexes?
Yes, up to five parts: add them with + Part. The weakest part at its reps limits the set, and the complex factor covers the chain.
Why are squats and deadlifts not on their own here?
A squat or a deadlift set on its own reads from its own PR, which this page does not ask for. Inside a snatch or clean & jerk complex they are priced from those lifts. The Nosto app keeps a PR for every movement and reads every set.
Why is the result sometimes a range?
Every factor that comes from coaching convention rather than measurement carries its own uncertainty. The calculator adds them up and shows the range instead of a falsely exact number. A single from your own PR is one number.
Is anything I type sent anywhere?
No. Everything is calculated in your browser, and your numbers are kept only in this browser so the page remembers them. The privacy page says what the site counts.
Sources
- NSCA, Essentials of Strength Training and Conditioning: the percentage-of-1RM table (squats, deadlifts, presses).
- Chapman et al., 2022: repetitions to failure in the hang power clean.
- Czaplicki and colleagues: measured power and hang variant ratios.
- Greg Everett, Olympic Weightlifting: A Complete Guide, and Catalyst Athletics programme percentages: complexes and pulls.
- The Nosto range model: lift ratios by strength and age, from published coaching ratios.
The factors are exported from the Nosto app, so the page and the app give the same number.