TR

1RM Calculator

Enter the weight you lifted and your rep count — instantly calculate your one rep max through 5RM.

kg

1 – 500 kg

reps

1 – 15 reps

Results

Target Weight % of 1RM

Formula: Wathan — 1RM = (100 × W) / (48.8 + 53.8 × e−0.075 × R)

VIGOR App

Track your 1RM automatically with every workout

VIGOR uses the Wathan formula to calculate your 1RM automatically from your logged sets and reps. Track weekly strength progress with graphs — core tracking free for life.

Core tracking free for life · No sign-up required