Free tool
How strong are you?
Free strength calculator. Enter a few lifts and see how you score against other lifters of your sex, bodyweight and age. It is the same body map Ratz builds from your logged workouts.
Put in the lifts you know. You'll get a score out of 100 for each muscle group, compared with other people who lift: same sex, same bodyweight, same age. No sign-up, and your numbers never leave your browser.
- Chest —
- Back —
- Shoulders —
- Legs —
- Glutes —
- Biceps —
- Triceps —
- Core —
Ratz does this from your workouts
Log your sets in the app and this map builds itself, with no numbers to type into a form. It keeps your history, shows your progress over time, and tells you what the next level takes in kilos. Guided tests cover the muscle groups your log can't measure, like core.
Download on the App StoreFree on iOS. Android coming soon. See how the strength map works →
How the score works
Each lift becomes an estimated one-rep max, divided by your bodyweight and corrected for body size. Strength doesn't grow in step with body mass, so a plain ratio would undersell heavier lifters. From 35 on, each year adds a little credit. The result lands on a scale for your sex: 0–24 Untrained, 25–49 Novice, 50–74 Intermediate, 75–99 Advanced, 100 Elite.
The comparison is with people who lift, not the general population. Intermediate is the middle of the gym, and plenty of people who have trained for years sit there.
A lift also credits the muscles it helps with. A bench press says something about your triceps and shoulders, so those score too, at a discount. Machines and cables are left out, because the same number on two different machines isn't the same weight.
These are estimates measured against published strength standards, not a fitness or health assessment.