openweightOpen Data Format for Strength Training

Your training data belongs to you, not to any one app

Migrate in One Command

Already using Strong or Hevy? Convert your entire training history to openweight with a single npx command. No code required.

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A clean, well-documented schema for workouts, templates, programs, and personal records. Human-readable and machine-validatable.

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TypeScript (npm) and Kotlin (Maven Central) SDKs for parsing, validating, and serializing workout data. Integrate in minutes.

SDK docs

Export from one app, import to another. Archive your training history in a format that will outlast any app. No vendor lock-in.

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