One Rep Max Calculator
Estimate your 1RM for any lift using a weight you've already moved. Get your full training percentage breakdown instantly.
| % of 1RM | Weight | Purpose |
|---|
What is a One Rep Max (1RM)?
Your one rep max is the maximum amount of weight you can lift for a single repetition with good form. It's the standard way to measure absolute strength in resistance training, and it's used to program training loads for strength, hypertrophy, and power.
Testing your true 1RM carries injury risk — especially for beginners. That's why 1RM estimation formulas exist: you lift a submaximal weight for multiple reps, and the formula predicts your maximum. These estimates are accurate to within about 5% for reps under 10.
How to use your 1RM for training
Once you have your estimated 1RM, you can set training loads as a percentage of that number. Different percentages target different training goals:
- 50–60%: Warm-up, technique work, active recovery
- 60–70%: Muscular endurance (15+ reps)
- 70–80%: Hypertrophy / muscle building (8–12 reps)
- 80–90%: Strength development (3–6 reps)
- 90–100%: Maximum strength, competition lifts (1–3 reps)
The formulas explained
Epley: weight × (1 + reps / 30) — most widely used, tends to be accurate for moderate rep ranges
Brzycki: weight × 36 / (37 − reps) — accurate for lower rep ranges (1–10)
Lander: (100 × weight) / (101.3 − 2.67123 × reps) — validated in research studies
Lombardi: weight × reps^0.10 — tends to give higher estimates, good for higher rep ranges
Average: Mean of all four formulas — reduces outlier bias
For best accuracy, use a weight you can lift for 3–8 reps with good form. Estimates become less reliable above 10 reps.
1RM strength standards by experience level
These figures are expressed as a multiple of bodyweight and give a rough sense of where your estimated 1RM sits relative to other lifters. They're general benchmarks, not targets — bodyweight, limb length, and training history all affect where you personally fall.
| Level | Squat | Bench Press | Deadlift |
|---|---|---|---|
| Novice (0–6 months) | 1.0× bodyweight | 0.75× bodyweight | 1.25× bodyweight |
| Intermediate (1–2 years) | 1.5× bodyweight | 1.0× bodyweight | 1.75× bodyweight |
| Advanced (3+ years) | 2.0× bodyweight | 1.5× bodyweight | 2.5× bodyweight |
| Elite / competitive | 2.5× bodyweight | 2.0× bodyweight | 3.0× bodyweight |
Deadlift 1RM is typically the highest of the three main lifts because it uses the most muscle mass and has the shortest range of motion relative to load. Bench press is usually the lowest, since it relies more heavily on smaller upper-body muscle groups. If your ratios differ significantly from these patterns, it often points to a specific strength or mobility limitation worth addressing.
Why your actual lift might not match your calculated 1RM
It's common to test a true 1RM and find it lower — or occasionally higher — than the number this calculator gave you. That gap almost always traces back to one of a few specific causes:
| What you notice | Likely cause | What to do |
|---|---|---|
| Missed the lift at the exact predicted weight | Neural fatigue from the warm-up sets, or the working set was closer to true failure than it felt | Rest 3–5 min between heavy warm-up sets; stop 1 rep short of failure on your test set |
| Actual max is well below the estimate | Rep set used to estimate was above 10 reps — formula error grows with rep count | Re-test using a set of 3–6 reps for a tighter estimate |
| Actual max is well above the estimate | Formula bias (e.g. Brzycki underestimates high-rep sets) or unusually high fast-twitch fiber ratio | Use the "Average of all" option, or the Lombardi formula for sets over 8 reps |
| Estimate feels right on some lifts, off on others | Technique-limited lifts (e.g. squat depth, bench pause) don't follow the same fatigue curve as simpler lifts | Trust the calculator less for technical lifts; weight it more for machine or single-joint movements |
| Number was accurate last month, feels wrong now | The estimate is only as fresh as the set it came from — strength shifts with training phase, sleep, and stress | Recalculate from a recent set rather than reusing an old number (see FAQ on retesting frequency) |
None of this means the calculator is unreliable — formula-based estimates are a starting point for programming, not a substitute for how a specific lift actually feels on a given day. Treat the number as the center of a range, not a fixed target.