Komga is a free and open source comics/mangas server.
- scan and index libraries (local folders) containing sub-folders with comic book archives in
cbrformat, as well as
- API to serve the individual pages of those books. It can convert pages to different image format on the fly.
- API to serve the complete file for download
- OPDS feed
- web interface
- web reader
- user management, with per-library access control
The easiest way to run Komga is via Docker. Please refer to the (instructions on how to use the image).
Alternatively you can run it from the fat
jar file. You can find them in the releases section.
In order to run Komga, use the following command:
java -jar komga-x.y.z.jar
Note that you need to have a valid
application.yml configuration file (or environment variables) for Komga to run properly, read on to the next section to find out more.
Komga relies heavily on Spring Boot's configuration, leveraging
profiles and configuration
The easiest way to configure is either via environment variables (a good fit for
docker-compose) or by using an
application.yml file located in the same folder as the
Each configuration key can have a different format depending if it's from the environment variable, or from the
application.yml file. In the following section I will provide both format in the form
In order to make Komga run, you need to specify some mandatory configuration keys (unless you use Docker, in which case defaults are setup):
prod- this will enable the database management and upgrades for new versions.
spring.datasource.url: the path of the database file. For Docker I use
/config/database.h2is the actual file inside the docker container. You can customize this part if running without docker.
You can also use some optional configuration keys:
komga.libraries-scan-cron: a Spring cron expression for libraries periodic rescans.
0 0 * * * ?will rescan every hour.
0 */15 * * * ?will rescan every 15 minutes. Defaults to
0 */15 * * * ?in
komga.threads.analyzer: the number of worker threads used for analyzing books. Defaults to
2. You can experiment to get better performance.
komga.libraries-scan-directory-exclusions: a list of patterns to exclude directories from the scan. If the full path contains any of the patterns, the directory will be ignored. If using the environment variable form use a comma-separated list.
komga.filesystem-scanner-force-directory-modified-time: if set to
true, it will force the last modified time of a directory as the maximum from its own last modified time and the last modified time from all the books inside the directory. This should be used only if your filesystem does not update the last modified time of a directory when files inside it are modified (Google Drive for instance).
komga.remember-me.key: a unique key. If set, the remember-me auto-login feature will be activated, and will generate a cookie with encoded login information to perform auto-login.
komga.remember-me.validity: the validity, in seconds, of the generated remember-me cookie. Defaults to 2 weeks.
What does it do?
Komga will scan your libraries for directories containing supported files (at the moment
- each folder containing comic books will be made as a
- each comic book file inside a
Serieswill be made as a
It works with sub-folders too, so if you have a structure like this:
Comics/ ├── Private Eye/ │ ├── Volume 1.cbz │ └── Volume 2.cbz └── One Shot.cbz
Komga will generate:
Seriescalled Comics, containing a
Bookcalled One Shot
Seriescalled Private Eye, containing two
Books called Volume 1 and Volume 2
On rescans, Komga will update Series and Books, add new ones, and remove the ones for which files don't exist anymore.
Then it will analyze each book, which consist of indexing pages (images in the archive), and generating a thumbnail.
At startup, if no user account exists in database, Komga will generate an initial administrator account with a random password, and will output the login and password in the logs:
2019-10-15 17:15:31.483 INFO 18808 --- [ restartedMain] o.g.k.i.scheduler.InitialUserController : Initial user created. Login: firstname.lastname@example.org, Password: 2Qf8l85xOB8o
If you want to open your Komga server outside your local network, it is strongly advised to secure it with
https (especially due to the use of http basic authentication).
Spring Boot supports
https out of the box, but you will have to configure it, and
https is most useful only with valid certificates (not self-signed), which most people don't readily have available.
Komga has an official extension for Tachiyomi, available from within Tachiyomi's extension menu.
The extension is configurable, you need to specify the
Komga should work with any OPDS reader, unfortunately most readers badly implement the OPDS protocol
Here is a list of reader applications I have tested:
|OS||App name||Status||OpenSearch support||Page streaming support|
|Android||FBReader: Favorite Book Reader||No||No|
|iOS||Chunky Comic Reader||No||Yes|
Feel free to report your findings with other readers (by sending a PR)!
The web interface is available on port
- browse libraries, series, and books
- search series and books
- download book file
- add and remove libraries (for administrators only)
- server settings (for administrators only)
- users management (add and remove user, edit user's shared libraries access)
- account settings
- change password
|Home page||Browse Series|
|Web reader||Web reader menu|
|Account settings||Users management||User rights|
Default port for APIs is
Komga offers a REST API, which you can browse using Swagger. It's available at
/swagger-ui.html. The API offers file download and page streaming.
In order to access the API, you will need to authenticate using Basic Authentication.
Komga offers a standard OPDS feed, it is available at
The OPDS feed also supports:
- OpenSearch functionality, to search by
- OPDS Page Streaming Extension 1.0