Workout apps collect unusually personal data: your weight, routines, progress and the days you stopped showing up. openGym asks a sensible question—why should any of that require an account on someone else's server?
A workout log that lives on your server
openGym combines weekly routine planning, guided sessions, set-by-set weight tracking, personal-record detection and body-weight charts. Its exercise library includes animated demonstrations, while the web app can be installed to a phone's home screen and continue working offline.
The project also supports passkey sign-in and synchronization between devices when it is self-hosted. That matters because a workout tracker has to be faster than a spreadsheet. If recording a set interrupts the session, ownership alone will not save the product.
Verified against the official repository and README. The project is licensed under AGPL-3.0.
What it can realistically replace
openGym targets the core job performed by apps such as Strong, Hevy and other workout loggers: remember the plan, show today's exercises, carry forward previous weights and make progress visible. It does not need to recreate every social, coaching or wearable feature to be useful.
The strongest case is not saving a few dollars. It is keeping a long-running personal record in a system you can back up, move and inspect without waiting for a data export.
Reserved for launch
The subscription disappears; the server does not
The software price is zero, but self-hosting still produces a bill. An existing home server makes the incremental cost small. Buying a new machine only for a workout log is much harder to justify.
- openGym software$0
- ServerExisting hardware or VPS
- Domain and HTTPSOptional, often useful
- BackupsYour responsibility
- Updates and troubleshootingYour time
This is therefore best viewed as another service on a server you already operate. On a multi-purpose home server, openGym can be close to free. As a standalone infrastructure project, it is an expensive way to avoid a modest app subscription.
“Docker Compose up” is only the beginning
The repository provides a Docker Compose path, which is the right starting point. A real deployment still needs persistent storage, backups, updates and a secure way to reach the application. Passkeys and phone synchronization also make HTTPS more than a cosmetic extra.
- Run it on an existing Docker host
- Keep it private on the home network initially
- Back up the application data directory
- Add HTTPS before depending on remote access
- Exposing an unpatched instance directly to the internet
- Treating sync as a substitute for backup
- Buying dedicated hardware before testing the demo
- Importing years of data without checking export options
Reserved for launch
The most important feature is still time
openGym is young. A polished feature list cannot yet answer how painless upgrades will be, how reliable offline synchronization feels after months of use, or how well the project handles a growing exercise history. Those are not accusations; they are the questions every new self-hosted application has to survive.
Anyone deeply invested in coaching, social feeds, watch integration or a particular workout ecosystem should also verify those workflows before migrating. openGym's appeal is focused: private planning and logging. That focus is a strength until a missing integration is central to your training.
The NoSub assessment
openGym is exactly the kind of project NoSub Tech exists to find: understandable, useful and aimed at a recurring frustration rather than a developer-only novelty. The current feature set is strong enough to justify a hands-on trial, particularly for someone already running Docker.
It is too early for an unconditional recommendation. The honest next step is to run it through several weeks of real training, test mobile sync and perform a full backup-and-restore cycle.