1RM - 1 Rep Max Calculator
New here? Start in order: BMR/TDEE → Macros → Body Fat % / LBM → 1RM.
Estimate your one-rep max (1RM) from a weight × reps set. Best accuracy is usually 1–10 reps.
lb
Estimated 1RM:
Lift:
Percent Table
| % | Estimated Load |
|---|
Tip: for programming, most people live around 65–85% depending on goal.
1RM Calculator
This calculator estimates your one-rep max (1RM) — the maximum weight you could lift for a single repetition — using a weight you lifted for multiple reps.
What 1RM is used for
- Setting training weights based on percentages (e.g., 70–85% for volume work).
- Tracking strength progress without maxing out frequently.
- Planning programs more accurately for barbell lifts.
How to use it
- Enter the weight you lifted.
- Enter the reps you completed with solid form.
- Click Calculate to estimate your 1RM and training percentages (if shown).
Accuracy notes
1RM estimates are most accurate in the 1–10 rep range. High-rep sets (12+ reps) are less reliable because fatigue and pacing influence the result more.
Note: Estimates for informational purposes only, not medical advice.