DuarteSantos8/openGym: Self-hosted gym & body-weight tracker — plan routines, log workouts (supersets, warm-ups, cardio), see which muscles are trained, fatigued or detrained, import from FitNotes/Strong/Hevy, passkey login. Your data, your server.

A self-hosted gym and body-weight tracker you actually own.

Plan your week, run guided workouts, log every set and your body weight,
on your phone, synced across your devices, behind your own passkey login.

Website · Live demo · Android APK · Self-hosting guide · Roadmap · Changelog

Home · today's workout and weight

Guided workout · demos and sets

Stats · heatmap, charts and PRs

Why openGym

Most workout apps keep your data on their servers, push you towards a subscription, or vanish when the company does. openGym runs on your own box, keeps your data in a folder you control, and is yours to fork. It still behaves like a modern app: installable on the home screen, passkey sign-in, works offline, syncs between your phone and your laptop.

No account on someone else's server, no subscription, no ads, no telemetry. One docker compose up and it's running.

The in-browser demo is the real app with example data, if you want to try it before installing anything.

Features

Planning

• A routine per weekday over a library of over 5,600 exercises with animated demos, searchable and

• Four starter plans (Push/Pull/Legs, Upper/Lower, Full Body, 5×5) that load as ordinary,

• Move a session to another day without touching the weekly plan. The week starts on Monday or

• Or skip the weekdays altogether: a rotation (A, B, C, A, ...) where the next session is

• Supersets, warm-up sets, drop sets and rest-pause, timed exercises (planks, hangs, carries),

• Your own exercises, with your own photo, GIF or short video. Location data is stripped on the

Training

• Guided sessions: today's workout starts itself, weights are pre-filled from last time, a rest

• A quiet workout screen: one menu per exercise, the set number as the set's own menu, card or

• Optional effort column as RIR or RPE, colour-coded, with a plain-language line per level.
• Plate math for barbell, EZ bar, trap bar and Smith machine, worked out from the plates you own.
• Bodyweight exercises know they carry no load: log reps, add a dip belt if you use one.
• Per-side reps for lunges and single-arm work, the screen stays awake while you train, and a

• Swipe a set left to delete it (with Undo) or right to copy it. Pyramid sets with their own reps

Progress

• Progression rules per routine or per exercise: linear, Greyskull LP, double progression through a

• Estimated 1RM per exercise with its own curve, Structural Balance ratios (Poliquin, Thibaudeau,

• A muscle map in three modes: where your volume went, what is still recovering, and what has gone

• Body-weight chart against a goal line, and progress photos on a timeline with a before/after

• Edit any saved workout after the fact, log one you did on paper, or move it to the right date.

Accounts and data

• Passkeys (Face ID, Touch ID, fingerprint) with per-profile data synced across devices. Password

• Two devices editing at once merge field by field instead of overwriting each other (see

• Import from FitNotes, Strong, Hevy (CSV or API key) and Apple Health weight exports. Export

• Share a plan as a small file or print it as a PDF.
• Optional admin dashboard with invite-only signup and an activity log.
• 19 languages, including right-to-left Arabic and Traditional Chinese. Exercise names and

Optional extras, off by default

• An AI coach that drafts a week of routines and later suggests changes based on

• An MCP server so an assistant like Claude Desktop can answer questions about your

The full list of what changed release by release is in the changelog.

Quick start

You need Docker with Compose.

git clone https://github.com/DuarteSantos8/openGym
cd openGym
cp .env.example .env
docker compose pull      # prebuilt images, amd64 + arm64 (skip this to build from source)
docker compose up -d

Open , tap Create profile, and you're in. The exercise animations are part of the image, so there's nothing else to download.

To reach it from your phone with passkeys you need HTTPS on a domain; that's a two-line change in .env. The self-hosting guide walks through Cloudflare Tunnel, Caddy, Traefik and nginx, and there are separate guides for HTTPS on a LAN and Kubernetes.

[!NOTE]

Images are published from the same tag to ghcr.io/duartesantos8/opengym-{api,web}

(what docker-compose.yml pulls) and registry.gitlab.com/duartesantos8/opengym/{api,web}. Swap

the image: lines if you prefer GitLab's registry, or run docker compose up -d --build to build

locally. Either way you don't need Node on the host.

Phone app

The same codebase builds a standalone app with Capacitor: no account, no server, everything stays on the phone, with native reminders and a rest countdown in the notification shade.

• Android: download the signed APK from the latest release

• iPhone: Apple doesn't allow installs outside the App Store. Self-host and add the PWA to your

Details and build instructions: docs/MOBILE.md.

How it works

• frontend/ is React 19 and Vite (React Router, Zustand), built to static files inside Docker.
• api/ is plain node:http with two dependencies: @simplewebauthn/server for passkeys and

• web/ builds the frontend and serves it with nginx, proxying /api so the whole app sits on

The training logic (progression rules, 1RM, how a logged session is read back) lives in pure functions under frontend/src/lib/ with tests beside them. The HTTP API is documented as an OpenAPI spec in api/openapi.yaml, browsable at opengym.ch/api.html.

How sync works

Each profile's data is one document with a server revision. A device sends the revision it last saw along with its changes; if another device wrote in between, the server refuses and returns the current document so the device can merge and retry. Every change carries its own stamp, down to a single setting or routine field, so the merge keeps the newest edit of each one and a deletion stays deleted.

Nothing that hasn't reached the server is discarded on disconnect or sign-out, and the app shows a banner whenever it's working offline.

Your data

Everything lives in ./data on your host:

| File | Contents | |---|---| | db.json | Profiles and public passkey data | | db.json.bak | A copy of the last good db.json, used if the main file can't be read | | state-.json | Each user's plan, workouts, body weight and settings | | audit.log | Admin activity log (no IP addresses unless you turn that on) | | secret | Session-cookie signing key |

Back up ./data and you've backed up everything. Passkey private keys never reach the server; they stay in your phone's secure hardware or your password manager.

Documentation

The documentation index sorts every guide by who it's for. The most used ones:

| I want to | Read | |---|---| | Get a quick answer | FAQ | | Set up my own instance | Self-hosting | | Use the Android or iPhone app | Phone app | | Bring my history from another app | Importing data | | Turn on the AI coach | AI coach | | Contribute code | Contributing | | Report a security problem | Security |

Roadmap

A release roughly every two weeks, each small and themed. The full plan is in ROADMAP.md, and the issues sit in the GitHub milestones. The next two releases finish the community wishes, then comes a new exercise database and a themed release every two weeks after it.

| Release | When | Theme | |---|---|---| | v1.3.10 | released Oct 2026 | New design, rotation, swipe actions, safer sync | | v1.3.11 | next | Fixes, about thirty community pull requests, Health Connect, measurements | | v1.3.12 | Nov 2026 | Community features: focus view, widget, timer rework | | v1.4.0 | Nov 2026 | A new exercise database | | v1.4.1 to v1.4.4 | Dec 2026 and Jan 2027 | Programmes, the progression engine, cardio | | v1.4.5 to v1.4.10 | Jan to Apr 2027 | Search, accounts, the iOS app, Android and health, looks | | later | | Database storage |

Community

• Discord for release announcements, self-hosting help and

• Discussions for questions and ideas

• Issues for reproducible bugs and agreed-on

• Pull requests are welcome; start with

Where the code lives

GitHub is the home of the project. gitlab.com/DuarteSantos8/opengym is a mirror, updated by a GitHub Actions workflow on every push to main and every release tag. It exists because its CI builds the release artifacts: the signed APK, the multi-arch images and the SBOMs. Nothing is merged there by hand. In the changelog, !NN refers to a GitLab merge request from the weeks in August and September 2026 when the project lived there.

How openGym is built

People have asked about this, so plainly: **openGym is developed with Claude Code**, Anthropic's coding agent. A large share of the code, tests and documentation is drafted in Claude Code sessions, and the repository carries a CLAUDE.md with the project context those sessions start from.

What that does and doesn't mean:

• A person decides and ships. What goes in, what gets reviewed and merged, and every release

• Tests hold the logic in place. The training logic is covered by unit tests, and pull requests

• The app itself doesn't need an LLM. Nothing in a default install calls an AI service. The AI

Community pull requests are written by their authors, with whatever tools they like, and reviewed the same way.

Support

openGym is free and stays free: AGPL, no paid tier, nothing held back for sponsors. If it replaced a paid tracker for you and you'd like to chip in, there's a coffee button below. A star, a bug report or a pull request helps just as much.

openGym's own code is licensed under the GNU AGPL v3.0. You can self-host, use, modify and share it; if you run a modified version as a network service, you have to offer that version's source under the same license.

[!IMPORTANT]

The exercise media is not covered by that license. The stills and animations are

© Aliaksandr Makatserchyk, Gym visual, licensed for use in openGym only:

180 px in this repository and on self-hosted servers, larger only inside the app packages. A

non-commercial fork may keep them unmodified with the notice; anything else needs your own licence

from gymvisual.com. The exercise text in catalogue/ is openGym's and open to contributions.

Full third-party notices, including the body-diagram geometry, are in NOTICE.md.