Turn sets into a reliable strength estimate. Pick your formula, units, and rounding preferences quickly. Use the plan to add weight with confidence weekly.
| Lifted Weight | Reps | RIR | Estimated 1RM (Average) | Training Max (90%) |
|---|---|---|---|---|
| 60 kg | 8 | 1 | ~80 kg | ~72 kg |
| 80 kg | 5 | 0 | ~93 kg | ~84 kg |
| 90 kg | 3 | 1 | ~105 kg | ~95 kg |
| 100 kg | 2 | 0 | ~107 kg | ~96 kg |
| 110 kg | 1 | 0 | 110 kg | 99 kg |
Example numbers are rounded and may vary by formula.
This tool estimates your one-rep max (1RM) from a submax set. It uses multiple published 1RM equations and lets you pick one or use an average.
RIR adjustment: If you enter reps-in-reserve, the calculator uses effective reps = reps + RIR before applying the formulas.
It converts a submax bench press set into an estimated one-rep max (1RM). Enter weight, reps, and optional RIR. The output includes a selected 1RM, a 90% training max, and working weights from 50% to 100% for practical programming.
Different equations fit different training populations and rep ranges. At low reps, results are usually close. At higher reps, the spread grows because fatigue tolerance varies. Using the “Average” option reduces outliers and often tracks weekly progress more smoothly.
Accuracy is strongest between 1 and 10 reps. Around 5 reps is a common sweet spot because technique stays stable while effort is high. When reps exceed 12–15, small changes in pacing or pause length can change output more than actual strength changes.
RIR (reps in reserve) estimates how many reps you could have done before failure. This tool uses effective reps = reps + RIR. For example, 80 kg × 5 with 2 RIR is treated like 7 effective reps, producing a higher but still reasonable 1RM estimate.
Percentages turn your estimated 1RM into training targets. As a rule of thumb: 70–75% supports volume, 80–85% builds strength, and 90–95% practices heavy singles or doubles. If you feel slow or unstable, drop 2.5–5% and keep form crisp.
Use the training max (90%) as your base. Week 1: 5×5 at ~75% TM. Week 2: 4×4 at ~80% TM. Week 3: 5×3 at ~85% TM. Week 4: 3×2 at ~90% TM, then retest an estimated 1RM.
If you enter bodyweight, the tool reports 1RM-to-bodyweight (e.g., 1.20× BW). This is useful for tracking relative strength during bulks or cuts. Compare only with consistent rules, like touch-and-go versus paused reps, and the same bar path.
Small setup changes can shift your bench by 2–10%. Keep feet planted, shoulder blades retracted, and bar path consistent. Use the same grip width and pause standard when possible. For safer testing, add a spotter and avoid grinding reps to failure.
If you want one stable number, choose Average. If you consistently train low reps, Epley or Brzycki often feel closer. The best choice is the one that matches your future performance when you test.
Use 1–10 reps for the best reliability. Five reps is a common benchmark. If you use 12+ reps, treat results as a trend indicator rather than a precise max.
RIR is how many reps you could still complete before failure. RIR 0 means you reached failure. RIR 2 means you stopped with two good reps left, so the estimate increases accordingly.
Technique, pauses, fatigue, and day-to-day readiness can reduce a true 1RM. High-rep sets also inflate some formulas. Use the training max and weekly estimates to track progress without needing frequent maximal attempts.
Use the smallest increment you can load. Many gyms use 0.5–1 kg jumps with microplates, or 2.5 lb jumps. Rounding keeps targets practical and helps match real plate loading.
Use that mode if it matches how you record training. Enter bar weight and the combined plates from both sides. The tool adds them to produce total lifted weight before applying the chosen 1RM formula.
Update after a hard top set once per week, using similar technique each time. Recalculate if you change tempo, add long pauses, or switch equipment. Testing a true 1RM every 8–16 weeks is enough for most lifters.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.