Calculate your 1RM with 4 validated formulas. Get DOTS & Wilks scores, strength standards benchmarking, a personalized training planner, and a reverse weight solver.
Your Lift
Optional — unlocks Wilks, DOTS & Strength Level
Estimated 1 Rep Max
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Enter your lift data on the left
Est. 1RM
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Training Max (90%)
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Strength Level
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BW Ratio
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Wilks Score
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DOTS Score
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—Avg of 4 formulasTraining Max: —
All Formula Estimates
Epley: —
Brzycki: —
Mayhew: —
Lombardi: —
Percentage-Based Training Zones
All weights based on your calculated 1RM. RPE = Rate of Perceived Exertion (10 = max effort).
% 1RM
Weight
Target Reps
Zone
Purpose
RPE
Rest
Intensity
Programming Templates
Computed from your 1RM. Training Max (TM) = 90% of 1RM per Wendler's recommendation.
Wilks Score (2020)
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Enter body weight to calculate
DOTS Score (IPF 2019)
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More equitable across body weights
Strength standards for Bench Press — Male. Based on bodyweight ratio benchmarks.
Level
BW Ratio
Benchmark
You
Gap
All 4 formulas plotted across rep counts using your entered weight. The dashed vertical line marks your current rep count.
Reps
Epley
Brzycki
Mayhew
Lombardi
Average
Reverse Solver — Find Your Training Weight
Given a target intensity (% of 1RM) and rep count, what weight should you load on the bar?
Recommended Weight
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Calculate your 1RM on the Calculator tab first
How to use: Set your target intensity (e.g., 80% for hypertrophy, 85-90% for strength) and your planned rep count. The solver shows the exact weight and rounds to the nearest 5 lbs/kg for practical plate loading.
How to Use This Calculator
1
Enter Your Lift
Input the weight you lifted and the reps you completed. Best accuracy comes from sets of 1–5 reps. Optionally add body weight for Wilks, DOTS, and strength level.
2
Choose Your Formula
Epley is most widely used. Brzycki is most accurate below 10 reps. Mayhew excels at 6–10 reps. Use "Average" for a balanced estimate across all methods.
3
Plan Your Training
The Training Planner tab shows all your working weights. Use the Reverse Solver to find what weight to load for any intensity and rep target.
Formula & Methodology
Epley Formula (1985)
1RM = Weight × (1 + Reps / 30)
The most widely cited formula. Tends to slightly overestimate at higher rep counts. Works well across all rep ranges.
Brzycki Formula (1993)
1RM = Weight × 36 / (37 − Reps)
Highly accurate for sets of 1–10 reps. The most commonly used formula in strength programming. Becomes unreliable above 10 reps.
Research-validated formula particularly accurate for 6–10 rep ranges. Uses an exponential decay model.
DOTS Score (IPF 2019)
DOTS = 500 × LiftKg / Polynomial(BodyWeightKg)
Adopted by the IPF (International Powerlifting Federation) in 2019. More equitable across all weight classes than Wilks, particularly at the extremes of body weight.
One Rep Max — the maximum weight you can lift for a single repetition with proper form and full range of motion.
Training Max (TM)
Typically 85–90% of your 1RM, used as the base for programming working sets. Reduces injury risk and provides recovery buffer.
RPE
Rate of Perceived Exertion — a 1–10 subjective effort scale. RPE 10 = true 1RM, RPE 8 = 2 reps in reserve, RPE 6 = 4+ reps remaining.
DOTS Score
An IPF-standardized score normalizing your lift relative to body weight using polynomial coefficients for male and female lifters.
Wilks Score
Classic powerlifting coefficient (2020 update) used to compare lifters across body weight classes. Higher is better.
Progressive Overload
Gradually increasing weight, reps, volume, or intensity over time to continuously challenge muscles and drive strength adaptation.
Real-World Examples
Example 1
Bench Press
Weight: 185 lbs × 5 reps (Epley)
1RM ≈ 215.8 lbs · Training Max ≈ 194 lbs · 80% = 173 lbs for hypertrophy work
Example 2
Squat
Weight: 275 lbs × 3 reps (Brzycki)
1RM ≈ 297 lbs · Training Max ≈ 267 lbs · 5/3/1 Week 1 top set ≈ 253 lbs
Using Your One Rep Max Effectively
Why Estimate Instead of Test
True 1RM testing carries injury risk and requires significant recovery. A heavy set of 3–5 reps provides a highly reliable estimate with much lower risk. Formulas are most accurate within 1–10 reps — use reps in this range for the best results.
Programming With Percentages
Most strength programs use percentages of 1RM to prescribe training weights. Jim Wendler's 5/3/1 uses 65–95% of a conservative Training Max. Linear progression programs work within the 80–90% range. Hypertrophy programs typically target 65–80%. Re-test every 4–8 weeks as strength improves.
When to Use Each Formula
Use Brzycki or the Average for general programming. Epley is useful as a quick mental calculation. Mayhew is best validated for 6–10 rep sets. Lombardi tends to be conservative and works well as a lower-bound estimate. If in doubt, the Average of all four formulas provides the most balanced and reliable estimate.
Accuracy Across Exercises
1RM formulas are most accurate for compound barbell movements — squat, bench press, and deadlift. They become less reliable for isolation exercises, machine movements, and rep ranges above 10. Factor in fatigue, technique, and equipment differences when comparing estimates to actual performance.
Frequently Asked Questions
Which 1RM formula is the most accurate?
No single formula is universally most accurate. Brzycki and Epley tend to perform best for rep ranges of 1-6, while Mayhew and Lombardi are more reliable for higher rep ranges (8-12). Using the average of multiple formulas, as this calculator does, reduces individual formula bias. For the most accurate estimate, use a weight you can lift for 3-5 reps rather than sets of 10+.
Should I actually attempt a true 1RM in the gym?
True 1RM testing carries higher injury risk than submaximal estimation, especially for beginners. It requires proper warm-up protocols, a spotter, and experience with heavy singles. Most training programs work perfectly well with estimated 1RM values. Competitive powerlifters and Olympic weightlifters may benefit from periodic true 1RM testing, but recreational lifters rarely need it.
Why does my estimated 1RM differ between exercises?
1RM formulas were developed primarily using compound barbell movements like bench press, squat, and deadlift. They become less accurate for isolation exercises (curls, lateral raises), machine movements, and exercises with high technique demands (Olympic lifts). Smaller muscle groups also fatigue differently than large ones, so a 10RM set of curls does not predict a 1RM as reliably as a 10RM set of squats.
What is the difference between DOTS and Wilks scores?
Both are bodyweight-relative strength coefficients used to compare lifters of different sizes. Wilks was the original standard in powerlifting but has been criticized for favoring certain weight classes. DOTS (Dots Official Total Score) was introduced in 2019 as an updated formula using more recent competition data. DOTS is now the official scoring system for the International Powerlifting Federation.
How often should I retest my 1RM?
For most intermediate lifters, updating your estimated 1RM every 4-8 weeks aligns well with typical training block lengths. Beginners may see changes every 2-4 weeks due to rapid neuromuscular adaptation. Rather than formally retesting, you can update your estimate whenever you hit a new rep PR at a given weight. Frequent true 1RM attempts are unnecessary and increase fatigue and injury risk.