How to Test Your 1RM Safely: A Step-by-Step Guide to Finding Your True Strength Max

The one-repetition maximum (1RM) is the maximum weight you can lift once with proper form. It's the gold standard for measuring absolute strength and is essential for program design (e.g., 'perform 8–10 reps at 75–85% of 1RM'). Measuring it periodically lets you objectively verify whether your training is producing real strength gains.

4–8 weeks

recommended testing interval

3–5 min

rest between attempts

① Perform 3–5 warm-up sets starting at 50%, progressing to 70%, 80%, 90%, then 95%. ② Rest 2–3 minutes between warm-up sets. ③ Limit the actual testing attempts to 3–5 max. ④ Stop immediately if the bar slows dramatically or form breaks down significantly (technical failure). ⑤ Starting 2.5–5 kg above your previous best minimizes the number of attempts needed.

For squats and bench press, always use a spotter or set safety bars. If testing alone, use the safety pins on a power rack or a Smith machine. Deadlifts are comparatively safer without a spotter since the bar can be lowered to the floor naturally.

If you're not ready for a direct max test, use an estimated 1RM formula. A popular option is the Epley formula: estimated 1RM ≈ weight × (1 + reps ÷ 30). For example, 100 kg for 5 reps gives 100 × (1 + 5/30) ≈ 117 kg. Accuracy is best at 5 reps or fewer; precision drops above 10 reps.

±5%

estimation error at ≤5 reps

±10%

estimation error at ≥10 reps