Enter Squat Data
Example Data Table
| Scenario | Weight | Reps | Method | Estimated 1RM | 90% Training Max |
|---|---|---|---|---|---|
| Intermediate volume set | 100 kg | 5 | Average of formulas | 116.00 kg | 104.50 kg |
| Heavier strength set | 120 kg | 3 | Average of formulas | 131.50 kg | 118.50 kg |
| Near-max single | 140 kg | 1 | Average of formulas | 143.50 kg | 129.00 kg |
Recent Calculation History
| Date | Weight | Reps | RIR | Effective Reps | Formula | 1RM | Training Max |
|---|---|---|---|---|---|---|---|
| No calculations yet. | |||||||
Formula Used
Epley
1RM = Weight × (1 + Effective Reps / 30)
Brzycki
1RM = Weight × 36 / (37 − Effective Reps)
Lombardi
1RM = Weight × Effective Reps0.10
Mayhew
1RM = 100 × Weight / (52.2 + 41.9 × e−0.055 × Effective Reps)
O'Conner
1RM = Weight × (1 + 0.025 × Effective Reps)
Wathan
1RM = 100 × Weight / (48.8 + 53.8 × e−0.075 × Effective Reps)
Effective reps are calculated as completed reps plus reps in reserve. This adjustment lets you estimate what the set might represent if you had pushed closer to failure.
Training max is calculated as estimated 1RM × selected training max percentage. Rounded load targets are then built from the preferred 1RM estimate.
How to Use This Calculator
- Enter the heaviest squat set you performed with solid depth and technique.
- Add the number of reps completed.
- Enter reps in reserve if the set stopped short of failure.
- Choose kilograms or pounds.
- Select your preferred formula or use the average of all formulas.
- Pick a training max percentage and your preferred plate rounding increment.
- Press the calculate button to show the result above the form.
- Review formula comparisons, load percentages, chart output, and session history.
- Use the CSV or PDF buttons to export your current result package.
Frequently Asked Questions
1. Which formula should I trust most?
Use the average when you want a balanced estimate. Use a specific formula when your coaching system already prefers one. Low-rep sets usually give tighter estimates than high-rep sets.
2. What does reps in reserve mean?
Reps in reserve estimates how many additional reps you could have completed. A set of five with two RIR behaves like roughly seven effective reps for estimation purposes.
3. Is this better than testing a true max?
It is safer and easier for frequent planning. A true max can be more exact, but estimated maxes reduce fatigue and still support solid programming decisions.
4. Why does the estimate range change across formulas?
Each formula models fatigue differently. Some formulas predict more aggressively from multiple reps, while others stay more conservative. The range helps you see that uncertainty.
5. What is a training max?
A training max is a reduced planning number, often around ninety percent of estimated one rep max. It creates more sustainable loading for volume, progression, and recovery.
6. Should I round to 2.5 or 5?
Use the increment that matches your available plates and gym setup. Smaller increments give finer progress, while larger increments are simpler in busy training environments.
7. Can I use this for front squats or box squats?
Yes, but keep movement style consistent. Use the same variation each time so your history, percentages, and progress comparisons stay meaningful and fair.
8. When should I avoid trusting the result?
Be cautious after shallow squats, poor bracing, rushed reps, unusual equipment changes, or sets far above ten effective reps. Those conditions can distort the estimate.