One Rep Max Calculator (1RM)

Calculate your max strength from any weight and rep count. Full training percentage table generated automatically.

Calculate Your 1RM

Estimated One Rep Max
0 lbs
Epley
0
Brzycki
0
Lander
0
Lombardi
0
% of 1RMWeightEst. RepsGoal

One Rep Max Calculator — Set Your Training Loads Scientifically

The one rep max (1RM) is the cornerstone of strength programming. Knowing your 1RM for any lift lets you set precise training weights for every goal: maximum strength, hypertrophy, power or muscular endurance. Directly testing a true 1RM carries injury risk at maximal loads, so the calculated estimate from a submaximal effort (a weight you can lift for 3-5 reps near failure) is the standard approach in most structured training programmes.

The Four 1RM Formulas

Our calculator uses four validated formulas simultaneously and displays the average as your working 1RM. Epley (1985): 1RM = weight x (1 + reps/30) — the most widely used, accurate across all rep ranges. Brzycki (1993): 1RM = weight / (1.0278 - 0.0278 x reps) — most accurate at 1-6 reps. Lander (1985): 1RM = (100 x weight) / (101.3 - 2.67123 x reps) — derived from competitive powerlifter data. Lombardi (1989): 1RM = weight x reps^0.1 — tends to estimate slightly higher than others. Use our macro calculator to set nutrition that supports the training loads you are lifting, and our calories burned calculator to quantify the energy demand of your strength sessions.

FormulaEquationBest ForOrigin
Epleyw x (1 + r/30)1-10 repsBoyd Epley, 1985
Brzyckiw / (1.0278 - 0.0278r)1-6 repsMatt Brzycki, 1993
Lander(100w) / (101.3 - 2.67r)1-8 repsLander, 1985
Lombardiw x r^0.11-10 repsLombardi, 1989

Training Zones by Percentage of 1RM

The NSCA (National Strength and Conditioning Association) defines training intensity zones based on percentage of 1RM. Each zone produces different physiological adaptations. Maximum strength: 85-100%, 1-3 reps, 3-5 min rest. Strength: 70-85%, 3-6 reps, 2-3 min rest. Hypertrophy (muscle size): 60-75%, 6-12 reps, 60-90 sec rest. Muscular endurance: 40-60%, 15+ reps, 30-60 sec rest. Power/speed: 30-60% performed explosively. The training percentage table below is automatically generated from your 1RM.

% of 1RMTypical RepsGoalRest Period
90-100%1-2Maximum strength4-5 min
80-90%2-4Strength3-4 min
70-80%4-8Strength-Hypertrophy2-3 min
60-70%8-12Hypertrophy60-90 sec
50-60%15-20Muscular Endurance30-60 sec
30-50%20+Endurance and Technique30 sec

Relative Strength Standards

Raw 1RM numbers mean different things at different body weights. Relative strength — your 1RM as a multiple of body weight — allows fair comparison across athletes. Squat: beginner 0.5-0.75x BW, intermediate 1.25-1.5x BW, advanced 1.75-2.0x BW, elite 2.0-2.5x BW. Bench Press: beginner 0.5x BW, intermediate 0.75-1.0x BW, advanced 1.25-1.5x BW. Deadlift: beginner 0.75-1.0x BW, intermediate 1.5-1.75x BW, advanced 2.0-2.5x BW. Women typically achieve 60-80% of these figures. Use our lean body mass calculator to express strength relative to lean mass rather than total body weight.

Periodisation Using Your 1RM

Linear periodisation progressively increases intensity (% of 1RM) across a training block. A 12-week block: weeks 1-4 at 65% for 4x10, weeks 5-8 at 75% for 4x6, weeks 9-11 at 85% for 5x3, week 12 testing at 90-100%. Re-testing your 1RM estimate at the end of each block recalibrates all percentages for the next block to reflect real strength progress. Undulating periodisation alternates intensity across the week (heavy, moderate, light days) and is preferred by many intermediate lifters. In both approaches, your 1RM is the reference that makes every session's specific weights meaningful rather than arbitrary.

Accuracy Tips and Common Mistakes

The most common mistake is using reps from a non-maximal set. If you completed 10 reps with weight still in reserve, that is not your 10-rep max and will significantly underestimate your 1RM. The formulas assume reps are taken to or very near failure. Use a 3-5 rep set taken to near-failure with good form for best accuracy. Avoid rep counts above 10 — at 12-20+ reps, endurance increasingly determines performance and estimates become unreliable. Treat the calculated 1RM as a range of plus or minus 5-10%, not an exact number. Your daily 1RM varies with sleep, nutrition, warm-up quality and readiness. Use our protein calculator to ensure daily protein intake matches your training demands.

Warm-Up Protocol Before Heavy Lifting

Progressive warm-up sets are essential before any high-percentage work. A standard protocol for a 100kg squat: empty bar x20, 40% x8, 60% x5, 75% x3, 85% x2, 92% x1 (last warm-up), then working set. Rest 3-5 minutes between the final warm-up sets. This protocol applies whether you are testing a true 1RM or completing a heavy top set at 85-90%. For submaximal 1RM estimation, follow the same warm-up protocol, stop at a weight you can complete 3-5 reps near failure, and enter those values into this calculator. Use our calories burned calculator to track the full energy cost of your training sessions.

1RM Testing vs Estimation

The calculated 1RM estimate from a submaximal set works well for programming throughout a training block. True 1RM testing is warranted in specific situations: competition preparation (where opening attempt selection requires accuracy within 1-2%); programme transitions (moving to a new training system with different percentage structures); and initial baseline testing when starting a structured strength programme. For everyone else following standard periodised training, the estimated 1RM updated every 4-6 weeks is accurate enough to set all training percentages and track progress effectively without the recovery demand or injury risk of true 1RM testing. When you do test a true 1RM, use 90-95% of your calculated estimate as the first attempt and increase by 2-3% increments from there. Use our protein calculator to set daily protein targets that match the volume and intensity you are training at, and our TDEE calculator to confirm total calorie intake supports recovery from heavy strength training.

Equipment and Its Effect on 1RM

Supportive equipment used in equipped powerlifting (squat suits, bench shirts, knee wraps) can add 10-30% or more to a lifter's 1RM compared to raw lifting. A raw deadlift 1RM of 200kg might become 220-240kg in a deadlift suit. This is why raw and equipped world records are tracked separately. For programming purposes, always use values from lifts performed under the same conditions you train in consistently. A raw 1RM estimate from a raw submaximal set gives you accurate percentages for all your raw training. If you occasionally train with knee sleeves but not full wraps, your effective 1RM with wraps will be somewhat higher, but the raw training percentages still apply to your sleeve training. Consistency in testing conditions matters more than the absolute number when using the 1RM as a programming reference point.

Programming Accessory Exercises with 1RM

While 1RM testing is most common for the squat, bench press and deadlift, the same formulas apply equally to any barbell or dumbbell movement. Your overhead press 1RM informs all shoulder pressing programming. Your barbell row 1RM helps balance pressing and pulling volume systematically. For dumbbell movements, enter the weight of one dumbbell into the calculator. The percentage table generated is universal: 75% of your dumbbell incline press 1RM for 8-10 rep hypertrophy sets works exactly the same way as 75% of your barbell bench 1RM. This removes the guesswork from accessory programming and ensures progressive overload is applied consistently across your entire programme rather than just the main movements. Re-test accessory 1RMs on the same schedule as your main lifts — every 4-6 weeks — to ensure all training loads stay calibrated as you get stronger. Use our lean body mass calculator to track whether your strength progress is accompanied by the muscle development you are training for, and our body fat calculator to monitor body composition changes alongside strength improvements over time. Beyond the big three lifts, the 1RM concept applies equally to any loaded movement where maximal force production is the goal. Athletes in sports outside powerlifting benefit from 1RM testing on sport-specific movements: a rugby player might test their hex bar deadlift and weighted chin-up 1RM; a basketball player their squat and single-leg press; a swimmer their lat pulldown and seated row. The percentage-based programming that flows from these 1RM estimates ensures training specificity and progressive overload are applied in the exact movements that transfer to on-field performance, rather than using arbitrary weights that may be too light to drive adaptation or too heavy to maintain technique across a full training set.

Frequently Asked Questions

What is a one rep max? +
A one rep max is the maximum weight you can lift for exactly one complete repetition with proper form. It is the gold standard measure of absolute strength in powerlifting and strength training, and the reference point from which all training loads are calculated.
Which 1RM formula is most accurate? +
The Epley and Brzycki formulas are the most widely validated. All four formulas are most accurate with 1-5 rep sets taken to near-failure. Above 10 reps, endurance factors reduce accuracy. Our calculator shows all four simultaneously and displays the average as your working 1RM.
What percentage of 1RM should I train at? +
Maximum strength: 85-100% (1-3 reps). Strength: 70-85% (3-6 reps). Hypertrophy: 60-75% (6-12 reps). Muscular endurance: 40-60% (15+ reps). Power: 30-60% performed explosively. The percentage table in our calculator is automatically generated from your 1RM result.
Is it safe to test your true 1RM? +
True 1RM testing is safe for experienced lifters with a spotter and proper progressive warm-up. For general fitness training, a calculated estimate from a 3-5 rep set is safer and sufficiently accurate. Start at 90-95% of your estimated max for a first true 1RM attempt.
How often should I test my 1RM? +
Every 4-8 weeks is typical for intermediate to advanced lifters following periodised programmes. Testing too frequently provides little useful data since strength gains occur over weeks. Most structured programmes include a testing week at the end of each 4-6 week training block.
What are good 1RM benchmarks? +
Intermediate standards as body weight multiples: Squat 1.25-1.5x BW, Bench Press 0.75-1.0x BW, Deadlift 1.5-1.75x BW. Advanced: Squat 1.75-2.0x BW, Bench 1.25-1.5x BW, Deadlift 2.0-2.5x BW. Women typically achieve 60-80% of these figures. These are for raw (no equipment) lifting.
Can I use this for any exercise? +
Yes, for any barbell or dumbbell exercise where you can count reps to near-failure. Most commonly used for squat, bench press, deadlift, overhead press and rows. For dumbbell exercises, enter the weight of one dumbbell. Always use reps from a set taken to or near failure for accurate results.

Related Calculators