1RM Calculator - One Rep Max

1RM Calculator - One Rep Max is a simple 1RM calculator for lifters. Enter the weight and reps from a set to estimate your one rep max (1RM) without testing a maximal lift.

Use it as a quick one rep max calculator during or after a workout, with kilograms or pounds.

Compare with strength standards
Compare your estimated 1RM with bodyweight-based strength standards. Use it as a strength level calculator: see your strength class, score, tier and division, and how close you are to the next strength rank.

Track your lift history
Save your lifts on your device and review your lift history. Compare previous estimates over time to follow changes in your strength.

Features
• One rep max calculator from weight and reps
• Kilograms or pounds
• Strength standards based on bodyweight
• Strength class, score, tier, division and progress
• Saved lifts and lift history

Built for lifters who want a simple strength calculator instead of a full gym tracker.

Recent changes:
Easier access to email feedback from settings.
Thoughtfully timed feedback prompts after successful use, with an in-app rating option.
Improved prompt limits that remember your choices across app restarts.