Kutt.to

Kutt is a modern URL shortener with support for custom domains. Create and edit links, view statistics, manage users, and more.

https://kutt.to

[!WARNING] kutt.it is NOT OWNED BY US. It could be a phishing site. We had the domain but it has been deactivated by the Italian TLD registrar due to the lack of identification documents, and now it's owned by someone else.

Please use kutt.to, all the previous and the future links work with this domain as well.

Table of contents

• Key features
• Donations and sponsors
• Setup
• Docker
• API
• Configuration
• Themes and customizations
• Browser extensions
• Videos
• Integrations
• Contributing

Key features

• Created with self-host in mind:
  • Zero configuration needed
  • Easy setup with no build step
  • Supporting various databases (SQLite, Postgres, MySQL)
  • Ability to disable registration and anonymous links
  • OpenID Connect (OIDC) login
• Custom domain support
• Set custom URLs, password, description, and expiration time for links
• View, edit, delete and manage your links
• Private statistics for shortened URLs
• Admin page to manage users and links
• Customizability and themes
• RESTful API

Donations and sponsors

Support the development of Kutt by making a donation or becoming an sponsor.

Donate or sponsor →

Setup

The only prerequisite is Node.js (version 20 or above). The default database is SQLite. You can optionally install Postgres or MySQL/MariaDB for the database or Redis for the cache.

When you first start the app, you're prompted to create an admin account.

1. Clone this repository or download the latest zip
2. Install dependencies: npm install
3. Initialize database: npm run migrate
4. Start the app for development npm run dev or production npm start

Docker

Make sure Docker is installed, then you can start the app from the root directory:

docker compose up

Various docker-compose configurations are available. Use docker compose -f <file_name> up to start the one you want:

• docker-compose.yml: Default Kutt setup. Uses SQLite for the database.
• docker-compose.sqlite-redis.yml: Starts Kutt with SQLite and Redis.
  • Required environment variable: REDIS_ENABLED
• docker-compose.postgres.yml: Starts Kutt with Postgres and Redis.
  • Required environment variables: REDIS_ENABLED, DB_PASSWORD, DB_NAME, DB_USER
• docker-compose.mariadb.yml: Starts Kutt with MariaDB and Redis.
  • Required environment variables: REDIS_ENABLED, DB_PASSWORD, DB_NAME, DB_USER, DB_PORT

Official Kutt Docker image is available on Docker Hub.

API

View API documentation →

Configuration

The app is configured via environment variables. You can pass environment variables directly or create a .env file. View .example.env file for the list of configurations.

All variables are optional except JWT_SECRET which is required on production.

You can use files for each of the variables by appending _FILE to the name of the variable. Example: JWT_SECRET_FILE=/path/to/secret_file.

Variable	Description	Default	Example
JWT_SECRET	This is used to sign authentication tokens. Use a long random string.	-	-
PORT	The port to start the app on	3000	8888
SITE_NAME	Name of the website	Kutt	Your Site
DEFAULT_DOMAIN	The domain address that this app runs on	localhost:3000	yoursite.com
LINK_LENGTH	The length of of shortened address	6	5
LINK_CUSTOM_ALPHABET	Alphabet used to generate custom addresses. Default value omits o, O, 0, i, I, l, 1, and j to avoid confusion when reading the URL.	(abcd..789)	abcABC^&*()@
DISALLOW_REGISTRATION	Disable registration. Note that if MAIL_ENABLED is set to false, then the registration would still be disabled since it relies on emails to sign up users.	true	false
DISALLOW_LOGIN_FORM	Disable login with email and password. Only makes sense if OIDC is enabled.	false	true
DISALLOW_ANONYMOUS_LINKS	Disable anonymous link creation	true	false
TRUST_PROXY	If the app is running behind a proxy server like NGINX or Cloudflare and that it should get the IP address from that proxy server. If you're not using a proxy server then set this to false, otherwise users can override their IP address.	true	false
DB_CLIENT	Which database client to use. Supported clients: pg or pg-native for Postgres, mysql2 for MySQL or MariaDB, sqlite3 and better-sqlite3 for SQLite. NOTE: pg-native and sqlite3 are not installed by default, use npm to install them before use.	better-sqlite3	pg
DB_FILENAME	File path for the SQLite database. Only if you use SQLite.	db/data	/var/lib/data
DB_HOST	Database connection host. Only if you use Postgres or MySQL.	localhost	your-db-host.com
DB_PORT	Database port. Only if you use Postgres or MySQL.	5432 (Postgres)	3306 (MySQL)
DB_NAME	Database name. Only if you use Postgres or MySQL.	kutt	mydb
DB_USER	Database user. Only if you use Postgres or MySQL.	postgres	myuser
DB_PASSWORD	Database password. Only if you use Postgres or MySQL.	-	mypassword
DB_SSL	Whether use SSL for the database connection. Only if you use Postgres or MySQL.	false	true
DB_POOL_MIN	Minimum number of database connection pools. Only if you use Postgres or MySQL.	0	2
DB_POOL_MAX	Maximum number of database connection pools. Only if you use Postgres or MySQL.	10	5
REDIS_ENABLED	Whether to use Redis for cache	false	true
REDIS_HOST	Redis connection host	127.0.0.1	your-redis-host.com
REDIS_PORT	Redis port	6379	6379
REDIS_PASSWORD	Redis password	-	mypassword
REDIS_DB	Redis database number, between 0 and 15.	0	1
SERVER_IP_ADDRESS	The IP address shown to the user on the setting's page. It's only for display purposes and has no other use.	-	1.2.3.4
SERVER_CNAME_ADDRESS	The subdomain shown to the user on the setting's page. It's only for display purposes and has no other use.	-	custom.yoursite.com
CUSTOM_DOMAIN_USE_HTTPS	Use https for links with custom domain. It's on you to generate SSL certificates for those domains manually—at least on this version for now.	false	true
ENABLE_RATE_LIMIT	Enable rate limiting for some API routes. If Redis is enabled uses Redis, otherwise, uses memory.	false	true
MAIL_ENABLED	Enable emails, which are used for signup, verifying or changing email address, resetting password, and sending reports. If is disabled, all these functionalities will be disabled too.	false	true
MAIL_HOST	Email server host	-	your-mail-server.com
MAIL_PORT	Email server port	587	465 (SSL)
MAIL_USER	Email server user	-	myuser
MAIL_PASSWORD	Email server password for the user	-	mypassword
MAIL_FROM	Email address to send the user from	-	[email protected]
MAIL_SECURE	Whether use SSL for the email server connection	false	true
OIDC_ENABLED	Enable OpenID Connect	false	true
OIDC_ISSUER	OIDC issuer URL	-	https://example.com/some/path
OIDC_POMPT	OIDC prompt	-	login
OIDC_CLIENT_ID	OIDC client id	-	example-app
OIDC_CLIENT_SECRET	OIDC client secret	-	some-secret
OIDC_SCOPE	OIDC Scope	openid profile email	openid email
OIDC_EMAIL_CLAIM	Name of the field to get user's email from	email	userEmail
OIDC_BUTTON_TEXT	OIDC login button text	Log in with OIDC	Log in via Example
REPORT_EMAIL	The email address that will receive submitted reports	-	[email protected]
CONTACT_EMAIL	The support email address to show on the app	-	[email protected]

Themes and customizations

You can add styles, change images, or render custom HTML. Place your content inside the /custom folder according to below instructions.

How it works:

The structure of the custom folder is like this:

custom/
├─ css/
│  ├─ custom1.css
│  ├─ custom2.css
│  ├─ ...
├─ images/
│  ├─ logo.png
│  ├─ favicon.ico
│  ├─ ...
├─ views/
│  ├─ partials/
│  │  ├─ footer.hbs
│  ├─ 404.hbs
│  ├─ ...

• css: Put your CSS style files here. (View example →)
  • You can put as many style files as you want: custom1.css, custom2.css, etc.
  • If you name your style file styles.css, it will replace Kutt's original styles.css file.
  • Each file will be accessible by <your-site.com>/css/<file>.css
• images: Put your images here. (View example →)
  • Name them just like the files inside the /static/images/ folder to replace Kutt's original images.
  • Each image will be accessible by <your-site.com>/images/<image>.<image-format>
• views: Custom HTML templates to render. (View example →)
  • It should follow the same file naming and folder structure as /server/views
  • Although we try to keep the original file names unchanged, be aware that new changes on Kutt might break your custom views.

Example theme: Crimson

This is an example and official theme. Crimson includes custom styles, images, and views.

Get Crimson theme →

View list of themes and customizations →

Homepage	Admin page	Login/signup

Usage with Docker:

If you're building the image locally, then the /custom folder should already be included in your app.

If you're pulling the official image, make sure /kutt/custom volume is mounted or you have access to it. View Docker compose example →

Then, move your files to that volume. You can do it with this Docker command:

docker cp <path-to-custom-folder> <kutt-container-name>:/kutt

For example:

docker cp custom kutt-server-1:/kutt

Make sure to restart the kutt server container after copying files or making changes.

Browser extensions

Download Kutt's extension for web browsers via below links.

• Chrome
• Firefox

Videos

Official videos

• Next.js to htmx – A Real World Example

Integrations

• ShareX – You can use Kutt as your default URL shortener in ShareX. If you host your custom instance of Kutt, refer to ShareX wiki on how to setup.
• Alfred workflow – Download Kutt's official workflow for Alfred app from alfred-kutt repository.
• iOS shortcut – Kutt shortcut for your apple device which works from the iOS sharing context menu or on standalone mode. A courtesy of @caneeeeee.

Third-party packages

Language	Link	Description
C# (.NET)	KuttSharp	.NET package for Kutt.to url shortener
C# (.NET)	Kutt.NET	C# API Wrapper for Kutt
Python	kutt-cli	Command-line client for Kutt written in Python
Ruby	kutt.rb	Kutt library written in Ruby
Rust	urlshortener	URL shortener library written in Rust
Rust	kutt-rs	Command line tool written in Rust
Node.js	node-kutt	Node.js client for Kutt.to url shortener
JavaScript	kutt-vscode	Visual Studio Code extension for Kutt
Java	kutt-desktop	A Cross platform Java desktop application for Kutt
Go	kutt-go	Go client for Kutt.to url shortener
BASH	GitHub Gist	Simple BASH function to access the API
BASH	url-shortener	Simple BASH script with GUI
Kubernetes/Helm	ArtifactHub	A Helm Chart to install Kutt on a Kubernetes cluster

Contributing

Pull requests are welcome. Open a discussion for feedback, requesting features, or discussing ideas.

Special thanks to Thomas and Muthu. Logo design by Muthu.