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
Coming soon
On the roadmap.
- Metri mobile app sync
- Cloud backup of your data
- Cross-device history
A native app is in the works.
Everything on Metri is free on the web today. We're building native iOS and Android apps with the same formulas, full offline support and synced progress. Here's what's coming.
- 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