Health & Medicine · Fitness · Strength Training
Deadlift Max Calculator
Estimates your one-rep maximum (1RM) deadlift from a submaximal lift using the Epley, Brzycki, or Lander formula.
Calculator
Formula
In all three formulas, w is the weight lifted (in kg or lb) and r is the number of repetitions performed. The Epley formula adds a fractional increment per rep. The Brzycki formula uses a ratio based on the rep ceiling of 37. The Lander formula applies a regression-derived percentage model. All three are most accurate when r is between 1 and 10.
Source: Epley B. (1985). Poundage Chart. Boyd Epley Workout. Lincoln, NE. | Brzycki M. (1993). Strength Testing—Predicting a One-Rep Max from Reps-to-Fatigue. JOPERD 64(1):88–90. | Lander J. (1985). Maximums Based on Reps. NSCA Journal 6(6):60–61.
How it works
A one-rep maximum represents the gold standard of absolute strength measurement in the deadlift. However, directly testing your true 1RM carries injury risk, requires significant recovery, and demands near-maximal neurological recruitment that can be stressful even for experienced lifters. Submaximal prediction equations solve this problem: you perform a set with a challenging but manageable weight for a controlled number of reps, then use a validated mathematical formula to project what you could lift for a single maximum effort.
This calculator supports three widely validated formulas. The Epley formula (1985) applies a linear scaling factor — for every rep above one, it adds 1/30th of the lifted weight to the projected maximum. The Brzycki formula (1993) uses a ratio model with a theoretical ceiling at 37 reps, and it tends to produce slightly more conservative estimates than Epley at lower rep counts. The Lander formula (1985) applies a regression-derived percentage model developed specifically from empirical strength data. All three are most accurate in the 1–10 rep range; accuracy degrades sharply above 10 reps as fatigue becomes a dominant variable that these models do not account for.
Beyond the 1RM estimate, this calculator also provides a rep-max table showing projected training weights for sets of 2, 3, 5, 8, and 10 reps. These are derived from commonly used percentage-based loading schemes and are practical for daily programming. A lifter with a 200 kg deadlift 1RM, for example, would program 5-rep sets at approximately 177.5 kg (88.75%) to build strength-endurance, or 3-rep sets at 185.5 kg (92.75%) to target near-maximal strength adaptation.
Worked example
Consider a lifter who pulls 140 kg for 6 repetitions using the Epley formula.
Step 1 — Apply the Epley formula:
1RM = 140 × (1 + 6 ÷ 30) = 140 × (1 + 0.2) = 140 × 1.2 = 168 kg
Step 2 — Verify with Brzycki:
1RM = (140 × 36) ÷ (37 − 6) = 5040 ÷ 31 ≈ 162.6 kg
Step 3 — Verify with Lander:
1RM = (100 × 140) ÷ (101.3 − 2.67123 × 6) = 14000 ÷ (101.3 − 16.027) = 14000 ÷ 85.273 ≈ 164.2 kg
The three formulas give estimates ranging from 162.6 to 168 kg. The spread is typical — for programming purposes, a conservative lifter might use the Brzycki estimate of 162.6 kg, setting their 5-rep training weight at 88.75% = approximately 144 kg.
Limitations & notes
These formulas are statistical estimates, not physiological measurements. Prediction accuracy drops significantly when reps exceed 10, as muscular endurance and fatigue become dominant factors the models do not capture. Each formula was developed on specific populations (often trained male athletes), so results may be less accurate for beginners, advanced lifters with unusual fatigue profiles, older adults, or female athletes with different relative endurance characteristics. Neural efficiency, grip strength, leverages, and fatigue state on a given day all affect the true 1RM independently of any formula. Never use these estimates to attempt an untested heavy single without an appropriate warm-up progression. The percentage-based rep-max table uses generalised population averages and will not perfectly reflect individual strength-endurance ratios — some lifters maintain higher percentages of 1RM across higher reps than others. This calculator does not account for the technical demands of the deadlift, including grip failure or lower-back fatigue, which often limit performance before muscular capacity is reached.
Frequently asked questions
Which 1RM formula is most accurate for the deadlift?
Research comparing the three formulas suggests the Brzycki and Lander equations tend to be slightly more accurate than Epley at moderate rep ranges (3–8 reps), with all three performing similarly when reps are kept to 5 or fewer. A 2012 meta-analysis by Reynolds et al. found that accuracy across all major 1RM equations is highest when the submaximal set is performed between 2 and 6 reps. When in doubt, average the three estimates for a robust projection.
How many reps should I perform for the most accurate 1RM estimate?
The most accurate estimates come from sets of 2–6 reps with a weight that is genuinely challenging — ideally between 80–95% of your true maximum. Sets of 10 or more reps introduce significant error because muscular endurance rather than peak strength becomes the limiting factor. For maximum accuracy, choose a weight you can lift for exactly 3–5 clean reps before failure.
Can beginners use this deadlift max calculator?
Beginners can use it, but should interpret results cautiously. Novice lifters often have underdeveloped neural efficiency and technique, meaning their submaximal rep performance may not translate linearly to a 1RM in the way the formulas assume. Additionally, beginners benefit more from building technique on moderate weights than from maximising absolute load, so the practical value of 1RM testing is lower early in training.
What is a good deadlift 1RM relative to bodyweight?
General strength standards suggest that lifting 1.5× bodyweight is a solid intermediate benchmark, 2× bodyweight is considered strong for most general-population athletes, and 2.5× or more is competitive-level strength. Elite powerlifters in lighter weight classes may deadlift 3× or more their bodyweight. These ratios vary by sex, age, and training history — women typically lift a slightly lower percentage of bodyweight than men on absolute standards but show similar relative progress rates.
How often should I retest my deadlift max?
For most strength athletes, retesting or re-estimating your 1RM every 4–8 weeks is appropriate — this aligns with common programming blocks (e.g., 4-week mesocycles). Rather than testing your true 1RM directly each time, performing a new submaximal test set and running it through this calculator reduces cumulative fatigue and injury risk. True 1RM testing is typically reserved for competition or peaking cycles, approximately 2–4 times per year.
Last updated: 2025-01-15 · Formula verified against primary sources.