Treat estimates as planning numbers
A calculated max is not the same as a tested max. It is best used to set training targets, compare trends, and avoid overshooting a block before it starts.
Strength estimate
One-rep max calculator
Enter the weight and reps from a hard set to estimate your current max and plan the next round of training.
Use the 1RM calculator
This page includes an interactive 1RM calculator for strength training. Open it in a browser to enter your numbers, switch units where supported, and save the result in Barbell Wiz.
- Use recent hard sets for better estimates.
- Keep reps in a realistic range for strength work.
- Pair the estimate with a conservative Training Max.
Track estimates over time
Barbell Wiz helps you look at progress from the lift history, not a single calculator result. The useful question is whether comparable work is trending up.
Reference
Epley one-rep max formula
This calculator uses the Epley estimate for sets of 1-20 reps. Treat the result as a planning number, not the same thing as a tested max.
Estimated 1RM = weight x (1 + reps / 30)Worked example
225 lb x (1 + 5 / 30) = 262.5 lb estimated 1RM
Epley rep chart
Approximate percentage of estimated 1RM represented by a hard set at each rep count.
| Reps | Set weight as % of e1RM | If the set was 225 lb |
|---|---|---|
| 2 | 93.8% | 240 lb e1RM |
| 3 | 90.9% | 247.5 lb e1RM |
| 5 | 85.7% | 262.5 lb e1RM |
| 8 | 78.9% | 285 lb e1RM |
| 10 | 75.0% | 300 lb e1RM |
| 12 | 71.4% | 315 lb e1RM |
Related
Keep building the same training system.
- CalculatorsTraining Max
Calculate a conservative Training Max from your one-rep max or estimated max, choose a percentage, and round the result to loadable weights.
- CalculatorsRPE calculator
Estimate strength from weight, reps, and RPE, then use the result to guide training loads, backoff work, and routine targets.
- TrackingRPE tracker
Track RPE, estimated maxes, top sets, backoffs, and strength progress with Barbell Wiz.
Put this number to work.
Use Barbell Wiz to put the number into routines, blocks, and real workout targets.