Instructions — One Rep Max

Calculating Your 1RM

Select a lift — Bench Press, Squat, Deadlift, or Pull-ups — then enter the weight you lifted and the number of reps you completed.

BarbellMax uses three research-backed formulas to estimate your one-rep max:

Epley — Best for 6–10 reps. Most widely cited formula, used by the NSCA.
Brzycki — Best for 1–5 reps. More conservative, preferred for lower rep ranges.
Wathan — Best for 5–10 reps. Uses exponential decay, considered highly accurate across rep ranges.

The large number displayed is the average of all enabled formulas. Toggle any formula on or off using its button to include or exclude it from the average.

For best accuracy, test with 3–7 reps at a weight near your limit. A warning appears if you enter more than 10 reps.

Manual Entry

Tap directly on the large 1RM number to type a known max. This lets you record a result from an actual 1RM attempt rather than an estimated one.

Pull-ups

Pull-ups require two inputs: your bodyweight and any added weight (belt, vest, etc.). The formula uses the total load.

Set added weight to 0 for bodyweight-only pull-ups — BarbellMax will log your max reps instead of estimating a 1RM, since an external load is needed to produce a meaningful prediction.

Deadlift Note

All standard formulas consistently underestimate deadlift 1RM due to grip, inertia from a dead stop, and posterior chain fatigue. Treat your deadlift estimate as a conservative floor — your actual max is likely higher. Use 2–5 reps for the best estimate.

Training Loads

Below your 1RM, every percentage from 95% down to 60% is shown with the corresponding weight. This is your programming reference for planning working sets.

Tap any row to instantly load that weight into the plate calculator on Load the Barbell.

Logging & History

Tap LOG to save the current entry to your Max Lift history for that exercise.

Each history entry shows the date, weight, reps, and calculated 1RM. From history you can:

Tap an entry to reload those numbers back into the calculator.
Tap the date on an entry to edit it.
Tap × to delete an entry.

History is also visible from the Max Lifts module on the Lifts & Runs page, where a Strength Progress line chart visualizes your 1RM trend over time for each exercise.

Max Lift Total (Max Load)

The combined total of your included lifts is shown in the Max Lift card. Use the Include in MAX LOAD total checkbox on each lift's detail panel to add or remove it from the total.

Bench Press, Squat, and Deadlift are included by default. Pull-ups are excluded. Your preference is saved automatically.

Units

Toggle between lbs and kg at the top of the page. All displayed values convert automatically. Your unit preference is saved and shared with the plate calculator.

One Rep Max Formula Science

Tap the One Rep Max Formula Science → button at the bottom of this page for the full research background, formula details, and accuracy notes behind every calculation.

Export Data for AI

Tap ⬇ Export data for AI at the bottom of any page to download a text snapshot of all your training data. Useful for sharing your 1RM history and programming with an AI assistant.

Sign In to Sync

Sign in from the Load the Barbell page using your Google account. Your 1RM history syncs automatically across all devices and the Android app.