Collaborate. Share! Publish!!!

When you create a new project in CoCalc, all of its files and folders are accessible only by you. You can add collaborators to work with you on the whole project - they will have read and write access. You can also grant read-only access (with the option to edit a copy) to individual files and folders for people who possess a secret link, or even publish these links in a way that makes them discoverable by search engines.


Projects are CoCalc’s way to organize collaboration. The owner of the project and added collaborators have equal access to all files, folders, and settings of the project, including ability to add new collaborators or remove existing ones. (The only exception to this rule is that it is impossible to remove the owner of the project.)

Not only your collaborators have access to the same files as you do, you can edit the same file at the same time with edits merged thanks to real time collaboration and merging of simultaneous edits. You can also chat with other users of the project.

To manage collaborators on the current project, go to Users tab.

Sharing Files and Folders

You can share individual files and folders with other people by sending them a link. To create it, use menu File > Publish File for an open file or in the file explorer select one file or folder using the checkbox on the left and click Publish button:

Publish a file using explorer

Publish a file using explorer

Next pick Public (unlisted). Yu can then copy the link to your clipboard using the button on the right of the link:

Publish a file without listing

Publish a file without listing

You may optionally enter a description for the file being shared, a copyright license, and even a custom name (see Vanity URLs to learn more). You can even tie your CoCalc license to the shared file - this way people who make their own copy of your content will be able to benefit from upgrades that it provides.

Shared files are marked with an icon in file explorer:

Published file in a file explorer

Published file in a file explorer

Publishing Files and Folders

In addition to creating links to access your files and folders, you can publish them on CoCalc share server where people can discover them directly or using search engines. Follow the same steps as for sharing above, but choose the Public (listed) option:

Publish a file with listing

Publish a file with listing

CoCalc Share Server

To view CoCalc files published by others, navigate to You can search for text in the title and contents of published files using the search box at upper right. You can sort the list of files by any of the columns listed, in increasing or decreasing order, by clicking in the column headings.

Share server home page

Share server home page

There is also a preview at the CoCalc home page, allowing people who are just learning about CoCalc to view a sample of published files.

When you open a sharing link, you get a view of the contents. Click Edit your own copy to copy a shared file or folder to a project that you own or collaborate on:

Opened sharing link

Opened sharing link

Vanity URLs

You can set up your profile so that all the documents you’ve published are listed under your unique URL,  (e.g.,

CoCalc lets you assign a username, project names, and file names, so that you can create links to shared files that are easy to type and remember.

If you set all these you get a nice url, e.g.

Starring Published Files

You can star published files on the share server and see everything you starred here:

Star a file on the share server

Star a shared file so you can find it easily later

You can undo the operation by clicking Starred:

remove previously-added star from a file on the share server

Click Starred to remove a previously-added star

Publishing Rendered GitHub Files

CoCalc share server offers a simple way to publish fully-rendered Jupyter notebooks and certain other file types in gists and GitHub repositories. All you need is a URL to the gist or repository you want to publish. Rendered document publishing is done by means of URL proxying (see Notes on URL proxying).

The URL schema is exactly the same as what uses, i.e., github/<github url> and gist/[github user]/[gist id]. Here are a couple of examples:

The main differences relative to nbviewer are:

Notes on URL proxying

Publishing Tips and Considerations

Test Your Publication

To make sure that what you have published works as expected, open the link while you are signed out of your CoCalc account or in a new incognito window (to avoid using your account).

Auxiliary Files

If your document depends on auxiliary files, e.g. images embedded in a markdown file, make sure these auxiliary files are accessible. To do this, put your document and all auxiliary files in a common folder and publish that folder.

Collections of Documents

If you want to publish multiple related files, e.g. notebooks accompanying your book, the best approach is likely to organize everything in a single folder, perhaps with subfolders for each chapter, and publish the top level folder. You still will be able to use links to individual chapters and/or notebooks!

Publishing the Whole Project

You can NOT publish your whole project and we have no plans to implement such a feature due to security considerations. If you want to work on the whole project with a trusted team, add them as collaborators instead!

Data Sets

Whenever feasible, you should host your data sets on CoCalc, either alongside your notebooks (if the data sets are small enough), or by making a request for global installation. This will ensure that your code will not break due to data sets becoming unavailable for one reason or another.

Interactive Elements

Interactive elements that use server processes, such as notebooks with Jupyter widgets and worksheets with Sage @interact, will not operate in files viewed from the share server. That is because documents on the share server are truly static. There is no kernel or Sage server running in the background to facilitate any sort of interactive computing. Controls that run completely in the browser work when served from the share server, for example 3d plots like this cardioid.

Duration of Software Support

If you are concerned that your code may stop working when software installed on CoCalc gets upgraded to its next version (which is very likely to happen sooner or later), you can pin a software environment in CoCalc with a reasonable expectation that it will be available for 5 years. Beyond that your notebooks and code still will be available, but may fail to work correctly without adjustments with newer versions of dependencies. To pin the environment, click Settings in the side panel and then pick a date-stamped Software Environment in the drop down:

Pin a software environment

Pinning a date-stamped software environment

Also, if you are concerned about your code working long term, consider adding software tests in addition to the main notebooks that focus on the content of your material!