About Metri

Metri is a free, open-source toolkit for people who take training seriously — accurate calculators and evidence-based guides, with no paywalls and no clutter.

What Metri is

Metri is web-first. Every calculator — 1RM, TDEE, macros, body fat, BMI, FFMI, hydration and plate loading — runs instantly in your browser, free, forever. Alongside them is a growing knowledge base of practical, no-nonsense guides on nutrition, training and recovery.

A native iOS and Android app is in development as an optional extra: the same tools, fully offline, with progress tracking and reminders. You never need it to use Metri — the web is the product.

Free and open source

Metri is MIT-licensed and developed in the open. There are no subscriptions, no locked features and no ads. You can read the code, file issues, suggest features or fork it entirely.

Keeping it open keeps it honest: the formulas behind every result are inspectable, so you can trust what the numbers mean.

Private by design

The calculators do their math locally — your numbers stay in your browser. An account is optional and only exists to sync saved results across devices and with the app.

Who builds it

Metri is built and maintained independently. Contributions are welcome — the best place to get involved is the GitHub repository.

Features

What you can do with Metri

Free tools and guides for serious lifters — no account needed to start.

17 instant calculators

1RM, TDEE, macros, body fat and more — results update as you type, and you can share or save any of them.

Evidence-based guides

A knowledge base on nutrition, training and recovery, with sources you can check.

Your account

Save calculation history and favorites, and track your account level.

Installable & offline

Add Metri to your device and run every calculator without a connection.

Command palette (⌘K)

Jump to any calculator, guide or page in a keystroke.

See a highlighted term anywhere? Tap it for a plain-English definition — likeTDEE·RIR·FFMI