What is xBrowserSync?

xBrowserSync API is the server-side REST service that powers xBrowserSync, a privacy-focused browser synchronization tool. It enables users to sync bookmarks and other browser data across different browsers and devices without creating accounts or sharing personal data. All data is encrypted on the client before transmission. The API can be self-hosted via Docker, Docker Compose (with MongoDB and Caddy reverse proxy), or manual Node.js installation. It requires MongoDB as a database and Node.js as the runtime. The service exposes a REST API on port 8080 by default, with configuration via JSON file and environment variables. The project is licensed under GPL-3.0 and accepts donations via Liberapay.

Should you self-host xBrowserSync?

xBrowserSync scores 54/100 on selfhost.directory (how scoring works) and ranks #17 of 46 in Bookmarks & Link Sharing. It has 855 GitHub stars.

There was no stable release in the past 12 months, so check the repository's recent activity before you rely on it.

Setup is moderate: expect some configuration beyond a single command. An official Docker image is available. It is GPL-3.0-licensed and written mostly in Typescript.

Its closest alternative on selfhost.directory is Karakeep (82/100, 30 114 stars). It scores higher overall, so compare the two before you pick. See xBrowserSync vs Karakeep side by side.

Features

Anonymous usage
Configurable sync limits
CORS Configuration
Cross-browser bookmark sync
End-to-end encryption
Geographic location tagging
HTTPS Support
Logging
Proxy Support
Rate Limiting
REST API
Service status messaging

How to configure xBrowserSync

dailyNewSyncsLimit3The maximum number of new syncs that a user can create per day.
The maximum number of new syncs that a user can create per day.
values: Integer, 0 to disable
db.authSourceadminThe database to use for authentication.
The database to use for authentication.
values: Database name
db.connTimeout30000The connection timeout period to use for MongoDB.
The connection timeout period to use for MongoDB.
values: Milliseconds
db.host127.0.0.1The MongoDB server address to connect to.
The MongoDB server address to connect to.
values: Hostname, IP address, or UNIX domain socket
db.namexbrowsersyncName of the MongoDB database to use.
Name of the MongoDB database to use.
values: Database name
db.passwordPassword of the account used to access MongoDB. Set as empty string to use environment variable XBROWSERSYNC_DB_PWD.
Password of the account used to access MongoDB. Set as empty string to use environment variable XBROWSERSYNC_DB_PWD.
values: String or empty for env var
db.port27017The port to use to connect to MongoDB.
The port to use to connect to MongoDB.
values: Port number
db.sslfalseConnect to MongoDB over SSL.
Connect to MongoDB over SSL.
values: true/false
db.usernameUsername of the account used to access MongoDB. Set as empty string to use environment variable XBROWSERSYNC_DB_USER.
Username of the account used to access MongoDB. Set as empty string to use environment variable XBROWSERSYNC_DB_USER.
values: String or empty for env var
db.useSRVfalseUse MongoDB's DNS Seedlist Connection Format to connect to the database.
Use MongoDB's DNS Seedlist Connection Format to connect to the database.
values: true/false
locationgbThe geographic location of the service, determined by an ISO 3166-1-alpha-2 code.
The geographic location of the service, determined by an ISO 3166-1-alpha-2 code.
values: ISO 3166-1-alpha-2 code
log.file.enabledtrueIf set to true, Bunyan will be used to capture minimal logging to file.
If set to true, Bunyan will be used to capture minimal logging to file.
values: true/false
log.file.levelinfoBunyan log level to capture.
Bunyan log level to capture.
values: trace, debug, info, warn, error, fatal
log.file.path/var/log/xBrowserSync/api.logFile path to log messages to.
File path to log messages to.
values: File path
log.file.rotatedFilesToKeep5Maximum number of rotated log files to retain.
Maximum number of rotated log files to retain.
values: Integer
log.file.rotationPeriod1dThe period at which to rotate log files.
The period at which to rotate log files.
values: String format $number$scope (ms, h, d, w, m, y) or named periods
log.stdout.enabledtrueIf set to true, Bunyan will be used to capture minimal logging to stdout.
If set to true, Bunyan will be used to capture minimal logging to stdout.
values: true/false
log.stdout.levelinfoBunyan log level to capture for stdout.
Bunyan log level to capture for stdout.
values: trace, debug, info, warn, error, fatal
maxSyncs5242The maximum number of unique syncs to be stored on the service.
The maximum number of unique syncs to be stored on the service.
values: Integer, 0 to disable
maxSyncSize512000The maximum sync size in bytes.
The maximum sync size in bytes.
values: Bytes
server.behindProxyfalseSet to true if service is behind a proxy, client IP address will be set from X-Forwarded-For header.
Set to true if service is behind a proxy, client IP address will be set from X-Forwarded-For header.
values: true/false
server.host127.0.0.1Host name or IP address to use for Node.js server for accepting incoming connections.
Host name or IP address to use for Node.js server for accepting incoming connections.
values: Hostname or IP
server.https.certPathPath to a valid SSL certificate. Required when HTTPS is enabled.
Path to a valid SSL certificate. Required when HTTPS is enabled.
values: File path
server.https.enabledfalseIf enabled, the service is started using HTTPS.
If enabled, the service is started using HTTPS.
values: true/false
server.https.keyPathPath to the SSL certificate's private key. Required when HTTPS is enabled.
Path to the SSL certificate's private key. Required when HTTPS is enabled.
values: File path
server.port8080Port to use for Node.js server for accepting incoming connections.
Port to use for Node.js server for accepting incoming connections.
values: Port number
server.relativePath/Relative path from the host where the service will be located.
Relative path from the host where the service will be located.
values: Path starting and ending with /
status.allowNewSyncstrueDetermines whether users will be allowed to create new syncs.
Determines whether users will be allowed to create new syncs.
values: true/false
status.messageMessage displayed in the service status panel of the client app.
Message displayed in the service status panel of the client app.
values: String (markdown supported)
status.onlinetrueIf set to false no clients will be able to connect to this service.
If set to false no clients will be able to connect to this service.
values: true/false
tests.dbxbrowsersynctestName of the MongoDB database to use for e2e tests.
Name of the MongoDB database to use for e2e tests.
values: Database name
tests.port8081Port to use for running tests.
Port to use for running tests.
values: Port number
throttle.maxRequests1000Max number of connections during throttle.timeWindow milliseconds before sending a 429 response.
Max number of connections during throttle.timeWindow milliseconds before sending a 429 response.
values: Integer, 0 to disable
throttle.timeWindow300000Amount of time (in milliseconds) before throttle counter is reset.
Amount of time (in milliseconds) before throttle counter is reset.
values: Milliseconds
XBROWSERSYNC_DB_PWDEnvironment variable for MongoDB password.
Environment variable for MongoDB password.
values: String
XBROWSERSYNC_DB_USEREnvironment variable for MongoDB username.
Environment variable for MongoDB username.
values: String