RepolveGet the appSkullcrusher estimated 1RM calculator.
Estimate your skullcrusher one-rep max from a completed set of 1–12 repetitions, then compare it with Repolve’s exercise benchmarks.
Calculate your skullcrusher score
Enter the total barbell weight, including the bar. Use a completed set of 1–12 reps. Inputs stay in your browser.
A worked skullcrusher example
Illustrative skullcrusher set: 25 kg for 8 completed repetitions. Use the load convention shown above and compare the same equipment and technique.
- Completed set
- 25 kg × 8 reps
- Estimated 1RM
- 31.7 kg
- Exercise score
- 45 · novice
Illustrative example using 80 kg bodyweight and male standards. Choosing female standards changes the exercise score, not the estimated max. This is one exercise score, not an overall Strength Score.
Skullcrusher rep-to-max examples
Each row uses a completed set at 25 kg. Enter the total barbell weight, including the bar. These are formula examples, not suggested loads to attempt.
| Completed reps | Estimated 1RM |
|---|---|
| 1 | 25.0 kg |
| 3 | 27.5 kg |
| 5 | 29.2 kg |
| 8 | 31.7 kg |
| 10 | 33.3 kg |
| 12 | 35.0 kg |
A one-rep set uses the entered load. Sets of 2–12 reps use weight × (1 + reps ÷ 30). The result estimates a single repetition; it is not a guarantee that you can lift that weight.
Muscles worked
The app lists triceps as the primary muscle group. In Repolve’s scoring model, this exercise supplies primary evidence for triceps. Training involvement and scoring coverage are different things.
Make your sessions comparable
Keep the same bar, bench angle and elbow position. Include the bar in your recorded total load.
How the estimate works
For a single rep, the estimate is the load entered. For 2–12 reps, the production engine uses the Epley estimate: weight × (1 + reps ÷ 30). It compares the resulting estimated max with bodyweight and the exercise’s sex-specific thresholds. This is an estimate from a completed set, not a prescription for your next attempt.
Skullcrusher strength standards
These ratios come directly from Repolve’s production standards. They describe exercise benchmarks, not population percentiles or age-adjusted rankings.
| Reference | Score | Male | Female |
|---|---|---|---|
| Beginner | 20 | 0.2× | 0.1× |
| Novice | 40 | 0.35× | 0.2× |
| Intermediate | 60 | 0.55× | 0.35× |
| Advanced | 100 | 0.8× | 0.55× |
| Elite | 125 | 1.1× | 0.75× |
Enter the total barbell weight, including the bar. The same unit must be used for the lift and bodyweight. Understand the standards
Track progression
Keep the completed load and repetitions alongside each estimate. Keep the same bar, bench angle and elbow position. Include the bar in your recorded total load. This page gives one exercise snapshot; saved workouts in Repolve let you follow your training history.
Learn how to compare strength progress · Understand your Strength Profile
Common variations
A dumbbell lying extension or cable extension uses a different setup. Record changes between straight and EZ bars rather than assuming identical performances.
Skullcrusher calculator questions
What weight should I enter?
Enter the total barbell weight, including the bar.
How should I compare skullcrusher sessions?
Keep the same bar, bench angle and elbow position. Include the bar in your recorded total load.
Can I substitute another variation?
A dumbbell lying extension or cable extension uses a different setup. Record changes between straight and EZ bars rather than assuming identical performances.
Related lift calculators
About this calculator
Written by Repolve to explain its own scoring model. Calculations and benchmark tables use the same engine and exercise standards as the app. Worked examples are illustrative, not customer results. Estimates describe logged performance; they do not directly measure muscle size or diagnose a training imbalance.