OSL 1RM Calculator

OFFICIAL STREETLIFTING
1RM Predictors
Switch tabs to change lift. Use Advanced for coach features.
STEP 1 — Master Bodyweight (applies to Muscle-Up / Pull / Dip)
kg
lb

Muscle-Up 1RM Predictor

Units
kg
lb
STEP 2 — Select Form Standard
Also estimate OSL Competition Form from this Training Form set.
Conversion factor: 92%
Fine-tune if needed. Moving the slider sets preset to Custom.
STEP 2 — Enter Lift Data
STEP 4 — Prediction Sensitivity (Optional)
You don’t need to touch this. Adjust only if you want more conservative or more generous predictions.
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STEP 5 — Calibration (Optional)
Calibrate to your true best 1RM (added weight) so predictions match your strength profile on this device.
Enable calibration
Estimated 1RM (added weight)
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Estimated OSL Competition Form (from training set)
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Estimated Combined Total
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Total = sum of all current 1RM predictions

Most 1RM calculators are just basic rep math.

They don’t account for how people actually train, and they often overestimate — especially from singles.

Basic Mode: Simple, fast, and realistic:

Enter weight + reps + RIR and get a grounded 1RM estimate.

It’s also anchored, meaning a true 1 rep @ 0 RIR returns the exact weight you lifted — no inflated single predictions.

Advanced Mode: This is what makes these different — and something you won’t find on typical calculators:

  • Prediction Sensitivity (optional) — adjust how aggressive or conservative estimates are

  • Calibration (optional) — match predictions to your real best 1RM so future estimates fit your strength profile

  • Form Type (Muscle-Up & Pull) — compare training reps vs strict OSL competition standard

  • Training → Competition conversion — estimate what your comp-legal lift would be based on training reps

Master Bodyweight System: For upper-body lifts, bodyweight is entered once and automatically applied across all relevant calculators. This keeps predictions consistent and removes repeated input.

Live Total Feature: As you use the calculators, your current predicted 1RMs are automatically combined into a running total at the bottom.

It updates instantly as you change inputs, giving you a real-time snapshot of your current strength profile across lifts.

Built for coaches and serious athletes — not generic one-size-fits-all numbers.