Track. Progress. Evolve.
The open-source training companion for serious lifters — 17 calculators and an evidence-based knowledge base, free and private by design.
- 17
- Free calculators
- 20+
- Evidence-based guides
- 0
- Accounts needed
- MIT
- Open-source (MIT)
Why Metri
Everything a lifter needs, free on the web.
No paywalls, no sign-up, no fluff — open-source tools you can actually trust. The app is just an optional extra.
17 instant calculators
1RM, TDEE, macros, body fat, BMI, FFMI, ideal weight, protein, heart-rate zones, Wilks/DOTS and more — each with a visual chart and a shareable link.
Macro Splitter
Open source forever
MIT-licensed and built in the open. Read the formulas, fork it, contribute.
View on GitHubWorks offline
The optional native app runs every tool with zero connection — your data stays on device.
Evidence-based guides
A growing knowledge base on nutrition, training and recovery — written for lifters, not clicks.
Browse the docsPrivate by design
Calculators run in your browser. An account is optional and only syncs what you choose to save.
Tools
Calculators & Tools
17 free calculators that run instantly in your browser — the most-used ones first, with the full set a click away.
See it the moment you type.
Every input recalculates instantly — no submit button. Results are colour-coded against healthy ranges and shareable in one tap.
- Instant — runs on every keystroke
- Colour-coded ranges and goals
- Share or save any result
Maintenance (TDEE)
2,759kcal
Example: maintenance calories, with cut / maintain / bulk targets.
Docs
Knowledge Base
An evidence-based, bilingual knowledge base — eight sections covering nutrition, training, recovery and more, written for lifters.
Plain-English, evidence-based.
Every guide explains the why — formulas, ranges and trade-offs — with sources you can check.
- Written for humans, not textbooks
- Cited, reviewed and kept current
How to read your BMI
BMI is a screening tool, not a diagnosis — it can't tell muscle from fat, which is why many athletes read as “overweight”.
Free account
Why create an account
Calculators are free for everyone — an account just remembers your work.
Guest
No sign-up needed.
- Every calculator, instantly
- No account required
- Nothing saved between visits
Free account
Free forever — no card.
- Save your calculation history
- Pin favorite calculators & guides
- Link Google or GitHub
- Sync across the web app
Premium
Free while in beta — Stripe checkout in progress.
- Automatic Metri mobile app sync
- Cloud backup of your data
- Unlimited devices, cross-device history
A native app is in the works.
Everything on Metri is free — web and app. The Android app is in beta today with the same formulas and full offline support, no account required; iOS is next. Optional account adds export/import, Premium adds sync.
- Instant calculators that run on every keystroke
- Works 100% offline — your data stays on device
- Progress photos, reminders and synced history
- Free and open source, forever
Push Day
Week 3 · 5 exercises
Bench 1RM
+8 kg
Protein
180/ 190 g
Built in the open Metri
Metri is MIT-licensed and free forever. Star it, fork it, or contribute on GitHub.
View on GitHub