One Rep Max Calculator: 1RM & Epley

Results

Estimated 1RM

115 kg

Average of Brzycki and Epley formulas. Use for programming intensity.

Wilks Score

Normalized strength vs. bodyweight (classic formula). Change bodyweight in the inputs to see this update.

Training Load Table (% of 1RM)

%	kg
95%	109
90%	103
85%	97
80%	92
75%	86
70%	80
65%	74
60%	69
55%	63
50%	57

Rep-Max Estimates

Reps	kg
2	111
3	108
4	105
5	102
6	99
7	95
8	92
9	89
10	86
11	83
12	80

One Rep Max Calculator: Strength Intelligence Engine

Your 1RM isn’t just a number—it’s the anchor for intelligent programming. These insights explain why estimation beats risky testing, how formulas differ, and how to use your 1RM for targeted training intensity.

1RM Intelligence

Direct vs Estimated 1RM: Why Estimation Wins

•Direct measurement means lifting to true failure—one rep, max load.

•That’s high-risk for beginners and unnecessary for programming. Estimation uses a safer sub-maximal set and a formula to predict your max—no failure required. You get a number accurate enough to design workouts without the injury risk. The step-by-step “how to find your one rep max using a sub-maximal set” lives in the article below; here, the takeaway is: when in doubt, estimate.

Why 1RM Matters: Targeted Training Intensity

•Without a 1RM, you’re guessing loads.

•Research shows that percentage-based programming produces more consistent progress than “feel.” Knowing your max lets you dial in the right intensity for your goal—whether that’s size, strength, or peaking. The exact percentage bands (e.g. 50–65% for endurance, 85–95% for strength) are in the article below; the principle is: one number unlocks your whole program.

Brzycki vs Epley: Two Formulas, One Answer

•Brzycki tends to be slightly conservative at higher reps; Epley can be slightly optimistic.

•This tool averages both so you get a middle-ground estimate. Don’t stress which formula is “right”—the math and comparison live in the Brzycki vs Epley section below; here, the takeaway is: use the average and focus on consistent retests rather than formula choice.

Wilks Score: Comparing Across Weight Classes

•An 80 kg lifter and a 120 kg lifter can’t be compared by raw kilos.

•Wilks (and IPF-style formulas) normalize strength to bodyweight so you can rank fairly. It’s vital for powerlifting comparisons and for tracking “relative” strength as you gain or lose weight. Enter bodyweight and gender in the calculator to see your normalized score; the article below covers how it fits into programming.

One Rep Max Calculator: Brzycki & Epley Formulas, 1RM Percentage Chart & Wilks Score

How to calculate 1RM with Brzycki and Epley formulas. Trusted by strength coaches. No sign-up—all calculations run locally.

What This Calculator Does & Who It's For

Calculator Purpose & Outputs

What You'll Get:

Estimated 1RM: Average of Brzycki and Epley formulas—your benchmark for all strength programming.
Training Load Table (1RM Percentage Chart): Weight targets at 50%, 55%, 60% … up to 95% of your 1RM so you can set intensity for specific workouts (e.g. 3×5 at 85%). Use this as your 1RM percentage chart for weightlifting.
Rep-Max Estimates: Theoretical weight limits for 2–12 reps to predict performance on higher-volume sets.
Wilks / IPF Score: Normalized strength-to-bodyweight ratio (optional; enter bodyweight and gender) for comparing across weight classes.
Save to Track: Store your result locally to monitor strength gains over time.
(This tool is for educational and programming use only. It does not replace professional coaching or medical advice.)
Formulas Used:

Brzycki Formula:
$\text{1RM} = \frac{\text{Weight}}{1.0278 - 0.0278 \times \text{Reps}}$
Epley Formula:
$\text{1RM} = \text{Weight} \times \left(1 + \frac{\text{Reps}}{30}\right)$
Reps 1–10 for reliability. Calculator averages both. Wilks uses classic coefficient with bodyweight (kg) and gender-specific constants.
Ideal Users:

Lifters programming by percentage: Need a 1RM estimate to set 70%, 85%, etc. without testing a true max.
Beginners: Learn how to calculate 1RM safely—avoid direct 1RM testing; use a 3–8 rep set and this estimator for safe, accurate programming.
Bench press max calculator / squat / deadlift: Use this tool as a bench press max calculator, squat max calculator, or deadlift 1RM estimator—select the exercise and enter weight and reps.
Coaches and athletes: Quick way to get training load tables and rep-max estimates for Squat, Bench, Deadlift, or other lifts.
Powerlifters: Estimate openers and training loads; add bodyweight for Wilks/IPF-style comparison.
Accuracy & Limitations:

Estimates are typically within ±3–5% when using 1–10 reps. Accuracy decreases above 10 reps—use a heavier weight for a better estimate. 1RM is exercise-specific; use the calculator separately per lift (e.g. bench press 1RM vs squat 1RM). This tool does not replace proper technique or professional guidance.

This one rep max calculator (1RM calculator) estimates your theoretical maximum for one repetition from a sub-maximal set—no lifting to true failure. Use it for bench press max, squat max, deadlift 1RM, or any lift. It provides a 1RM percentage chart for weightlifting (training load table), rep-max estimates, and optional Wilks score.

How to Calculate 1RM Safely: Direct vs Estimated 1RM

Direct vs Estimated 1RM

Direct 1RM Testing:

You work up to a single maximal rep. Pros: True max for competition or peaking. Cons: High injury risk, requires technique and experience, and is unnecessary for most trainees who only need a number for programming.
Estimated 1RM (This Tool):

You perform a hard set of 1–10 reps (ideally 3–8), then enter weight and reps. Pros: Safe, no failure required, accurate enough for setting 50%–95% training loads. Cons: Slight formula variance (±3–5%); not a “competition max” unless you’re very close to 1–2 reps.
How to Find Your One Rep Max Using a Sub-Maximal Set:

Step 1: Choose the exercise (e.g. Bench Press).
Step 2: Warm up, then perform one hard set of 3–8 reps with a weight you could not do more than 10 reps with.
Step 3: Enter the weight lifted and number of reps completed.
Step 4: Use the estimated 1RM and the training load table to set your next workouts (e.g. 3×5 at 85%).
Step 5: Retest in 4–8 weeks with a similar sub-maximal set and compare saved results.

How to calculate 1RM safely: avoid direct testing if you’re a beginner. Direct measurement means lifting the maximum weight you can for one rep—high effort and higher injury risk. Estimation uses a safer, sub-maximal set and a formula (Brzycki or Epley) to predict your max. Here’s how they differ and when to use each.

Why 1RM Matters: 1RM Percentage Chart for Weightlifting & Targeted Intensity

Using Your 1RM for Programming

1RM Percentage Chart: Guidelines (2026 Exercise Science Standards):

50–65% of 1RM: Endurance, technique practice, warm-ups.
65–75% of 1RM: Hypertrophy (size), higher reps (8–12).
75–85% of 1RM: Strength and hypertrophy blend (5–8 reps).
85–95% of 1RM: Strength focus (1–5 reps).
90%+ of 1RM: Peaking, openers, low volume.
The training load table in this one rep max calculator gives you exact weights for each percentage so you can program consistently and avoid overtraining.
Rep-Max Estimates:

The “Rep-Max Estimates” table shows the theoretical weight you could lift for 2, 3, … 12 reps based on your estimated 1RM. Use it to choose working weights for sets of 5, 8, or 10 without testing each rep range to failure.
Why Consistency Beats Guessing:

Programs built on percentages of 1RM produce more predictable progress than “lift until it feels hard.” Retest your estimated 1RM every 4–8 weeks and update your training loads; use the save feature to track progress over time.

Knowing your 1RM allows you to manage “targeted training intensity”—the right load for your goal. Too light and you don’t adapt; too heavy and you risk overtraining or injury. A 1RM percentage chart for weightlifting (the training load table in this calculator) removes the guesswork.

Brzycki vs Epley Formula: Which Is Best?

Comparing the Two Formulas

Brzycki Formula:

$\text{1RM} = \frac{\text{Weight}}{1.0278 - 0.0278 \times \text{Reps}}$
Often slightly lower at higher reps (8–10). Widely used in strength and conditioning.
Epley Formula:

$\text{1RM} = \text{Weight} \times \left(1 + \frac{\text{Reps}}{30}\right)$
Can be slightly higher at higher reps. Simple; used in research and apps.
Why We Average Them:

Averaging Brzycki and Epley reduces formula-specific bias and aligns with current practice in 2026 exercise science standards. For 3–8 reps, both formulas agree closely; the average gives a robust single number for programming.

Both Brzycki and Epley are well-validated for sub-maximal 1RM estimation. This calculator uses the average of both for a balanced result. Understanding each helps you interpret the output.

Wilks Score & IPF: Comparing Strength Across Weight Classes

What Is Wilks Score and When to Use It

Why Wilks Matters:

Heavier lifters typically lift more in absolute terms; a 120 kg lifter’s raw total will exceed an 80 kg lifter’s. Wilks applies a bodyweight-based coefficient so you can rank fairly. Used in powerlifting to crown overall winners across weight classes.
How This Calculator Uses Wilks:

Enter your bodyweight and gender in the optional Wilks section. The tool uses the classic Wilks formula (500 denominator) with your estimated 1RM to produce a normalized score. Use it to compare your strength to others or to track “relative” strength as you gain or lose weight.
Wilks vs IPF GL:

This calculator uses the classic Wilks coefficient. The IPF (International Powerlifting Federation) has adopted newer formulas (e.g. IPF GL); for official meets, refer to current federation rules. For training and comparison, the classic Wilks score remains widely understood.

A Wilks score (or IPF-style points) normalizes strength to bodyweight so you can compare lifters across weight classes. This one rep max calculator optionally computes your Wilks score when you enter bodyweight and gender—useful for powerlifting and for tracking relative strength over time.

FAQ

? Is the 1RM calculator accurate?

Yes, within limits. Sub-maximal 1RM estimators (Brzycki, Epley) are typically within ±3–5% of a true 1RM when you use 1–10 reps. Accuracy drops above 10 reps. This tool averages Brzycki and Epley for a balanced estimate. Use it to set training intensity, not to replace proper testing if you need a competition max.

? How many reps are best for estimating 1RM?

3–8 reps give the most reliable estimates. 1–2 reps are very accurate but require near-maximal effort. 9–10 reps still work but formulas become less precise. Above 10 reps, use a heavier weight for a better estimate—formulas were validated on low-rep sets.

? Can I use the same 1RM for every exercise?

No. Your 1RM is specific to each lift. A bench press 1RM does not predict your squat or deadlift 1RM. Use this calculator separately for each exercise (Squat, Bench Press, Deadlift, etc.) and program intensity per lift.

? What is the Brzycki vs Epley formula?

Brzycki: 1RM = Weight ÷ (1.0278 − 0.0278 × Reps). Epley: 1RM = Weight × (1 + Reps ÷ 30). Both estimate 1RM from a sub-maximal set. Brzycki tends to be slightly lower at higher reps; Epley can be slightly higher. This calculator averages both for a balanced result.

? How do I calculate 1RM safely?

Avoid testing a true 1RM (lifting to failure) if you’re a beginner. Instead, do a hard set of 3–8 reps with good form and enter the weight and reps here. The estimate is safer and accurate enough for programming. Save the result to track progress over time.

? What is a Wilks score?

Wilks (or IPF-style) score normalizes strength across bodyweight. Heavier lifters usually lift more in absolute terms; Wilks lets you compare lifters of different sizes. Enter your bodyweight and gender to see your normalized score. Used in powerlifting to rank across weight classes.

? Why does 1RM matter for training?

Knowing your 1RM lets you set “targeted training intensity.” For example, 70% of 1RM for hypertrophy, 85% for strength, 90%+ for peaking. Without an estimate, you’re guessing loads. This tool gives you a percentage-based roadmap (50%–95% of 1RM) so you can program precisely.

? What is direct vs estimated 1RM?

Direct 1RM means you actually lift the maximum weight for one rep—high effort and higher injury risk. Estimated 1RM uses a sub-maximal set (e.g. 5 reps) and a formula to predict your max. Estimation is safer and sufficient for most trainees; direct testing is for competition or advanced peaking.

One Rep Max Calculator: Brzycki & Epley, Training Load Table & Wilks

Strength Biometrics

Wilks / IPF Score (optional)