An HTML5 VNC client


101.0.04 years ago4 years agoMinified + gzip package size for @hostnet/novnc in KB


fork provides compatibility with ES5

noVNC: HTML VNC Client Library and Application

Build Status


noVNC is both a HTML VNC client JavaScript library and an application built on top of that library. noVNC runs well in any modern browser including mobile browsers (iOS and Android).

Many companies, projects and products have integrated noVNC including OpenStack, OpenNebula, LibVNCServer, and ThinLinc. See the Projects and Companies wiki page for a more complete list with additional info and links.

Table of Contents


The project website is found at novnc.com. Notable commits, announcements and news are posted to @noVNC.

If you are a noVNC developer/integrator/user (or want to be) please join the noVNC discussion group.

Bugs and feature requests can be submitted via github issues. If you have questions about using noVNC then please first use the discussion group. We also have a wiki with lots of helpful information.

If you are looking for a place to start contributing to noVNC, a good place to start would be the issues that are marked as "patchwelcome". Please check our contribution guide though.

If you want to show appreciation for noVNC you could donate to a great non- profits such as: Compassion International, SIL, Habitat for Humanity, Electronic Frontier Foundation, Against Malaria Foundation, Nothing But Nets, etc. Please tweet @noVNC if you do.


  • Supports all modern browsers including mobile (iOS, Android)
  • Supported VNC encodings: raw, copyrect, rre, hextile, tight, tightPNG
  • Supports scaling, clipping and resizing the desktop
  • Local cursor rendering
  • Clipboard copy/paste
  • Licensed mainly under the MPL 2.0, see the license document for details


Running in Firefox before and after connecting:


See more screenshots here.

Browser Requirements

noVNC uses many modern web technologies so a formal requirement list is not available. However these are the minimum versions we are currently aware of:

  • Chrome 49, Firefox 44, Safari 10, Opera 36, IE 11, Edge 12

Server Requirements

noVNC follows the standard VNC protocol, but unlike other VNC clients it does require WebSockets support. Many servers include support (e.g. x11vnc/libvncserver, QEMU, and MobileVNC), but for the others you need to use a WebSockets to TCP socket proxy. noVNC has a sister project websockify that provides a simple such proxy.

Quick Start

  • Use the launch script to automatically download and start websockify, which includes a mini-webserver and the WebSockets proxy. The --vnc option is used to specify the location of a running VNC server:

    ./utils/launch.sh --vnc localhost:5901

  • Point your browser to the cut-and-paste URL that is output by the launch script. Hit the Connect button, enter a password if the VNC server has one configured, and enjoy!

Integration and Deployment

Please see our other documents for how to integrate noVNC in your own software, or deploying the noVNC application in production environments:

  • Embedding - For the noVNC application
  • Library - For the noVNC JavaScript library


  • Core team:

  • Notable contributions:

    • UI and Icons : Pierre Ossman, Chris Gordon
    • Original Logo : Michael Sersen
    • tight encoding : Michael Tinglof (Mercuri.ca)
  • Included libraries:

    • base64 : Martijn Pieters (Digital Creations 2), Samuel Sieb (sieb.net)
    • DES : Dave Zimmerman (Widget Workshop), Jef Poskanzer (ACME Labs)
    • Pako : Vitaly Puzrin (https://github.com/nodeca/pako)

Do you want to be on this list? Check out our contribution guide and start hacking!

If you find any bugs or have a feature request, please open an issue on github!

The npm package download data comes from npm's download counts api and package details come from npms.io.