SageMath, Inc.

CoCalc Subscriptions and Pricing (September 2016)

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Initially, you start using CoCalc under a free plan. There are various subscription options available to improve the service in various ways. Listed prices are in US dollars (when charging in local currency, the prices are converted into local currency using the conversion rates published by leading financial institutions).

When logged in, you may sign up for a subscription in the billing tab and see a summary of upgrades in the upgrades tab.


Your work on CoCalc happens inside projects. You may create any number of independent projects. They form your personal workspaces, where you privately store your files, computational worksheets, and data. You typically run computations through the web-interface, either via a worksheet, notebook, or by executing a program in a terminal (you can also ssh into any project). You can also invite collaborators to work with you inside a project, and you can explicitly make files or directories publicly available to everybody.

Shared Resources

Each projects runs on a server, where it shares disk space, CPU, and RAM with other projects. Initially, projects run with default free quotas on heavily used free machines that are rebooted frequently. You can upgrade any quota on any project on which you collaborate, and you can move projects to faster very stable members-only computers, where there is much less competition for resources. If a project on a free computer is not used for a few weeks, it gets moved to secondary storage, and starting it up will take longer; in contrast, projects on members-only computers always start up very quickly.

Quota upgrades

By purchasing one or more of our subscriptions, you receive a certain amount of quota upgrades.
  • You can upgrade the quotas on any of your projects up to the total amount given by your subscription(s) and the upper limits per project.
  • Project collaborators can collectively contribute to the same project, in order to increase the quotas of their common project — these contributions benefit all project collaborators.
  • You can remove your contributions to any project (owner or collaborator) at any time.
  • You may also subscribe to the same subscription more than once, in order to increase your total amount of quota upgrades.
Please immediately email us at [email protected] if anything is unclear to you.
Free plan
low-grade Server hosting
no Internet access
1 hour  Idle timeout
1 GB  Memory
3 GB  Disk space
1 share  CPU shares
1 core  CPU cores

$ 0

Maximum possible quotas per project
1 upgrade Member hosting
1 upgrade Internet access
90 days Idle timeout
8 GB Memory
50 GB Disk space
8 shares CPU shares
4 cores CPU cores

Personal subscriptions

We offer several subscriptions that let you upgrade the default free quotas on projects. You can distribute these upgrades to your own projects or any projects where you are a collaborator — everyone participating in such a collective project benefits and can easily change their allocations at any time! You can get higher-quality hosting on members-only machines and enable access to the internet from projects. You can also increase quotas for CPU and RAM, so that you can work on larger problems and do more computations simultaneously.
Standard plan
2 upgrades Member hosting
20 upgrades Internet access
1 day Idle timeout
3 GB Memory
5 GB Disk space
0.5 shares CPU shares

$ 7 / month
$ 79 / year

Premium plan
16 upgrades Member hosting
80 upgrades Internet access
8 days Idle timeout
24 GB Memory
40 GB Disk space
4 shares CPU shares
2 cores CPU cores

$ 49 / month
$ 499 / year

Professional plan
40 upgrades Member hosting
200 upgrades Internet access
20 days Idle timeout
60 GB Memory
100 GB Disk space
10 shares CPU shares
5 cores CPU cores

$ 99 / month
$ 999 / year

Course packages

We offer course packages to support teaching using CoCalc. They start right after purchase and last for the indicated period and do not auto-renew. Following this guide, create a course file. Each time you add a student to your course, a project will be automatically created for that student. You can create and distribute assignments, students work on assignments inside their project (where you can see their progress in realtime and answer their questions), and you later collect and grade their assignments, then return them.

Paying is optional, but will ensure that your students have a better experience, network access, and receive priority support. The cost is between $4 and $9 per student, depending on class size and whether you or your students pay. Start right now: you can fully setup your class and add students immediately before you pay us anything!

Your or your institution pays

You or your institution may pay for one of the course plans. You then use your plan to upgrade all projects in the course in the settings tab of the course file.

Students pay

In the settings tab of your course, you require that all students pay a one-time $9 fee to move their projects to members only hosts and enable full internet access.

Small course plan
25 upgrades Member hosting
50 upgrades Internet access

$ 199 / 4 months
$ 499 / year

Medium course plan
70 upgrades Member hosting
140 upgrades Internet access

$ 399 / 4 months
$ 999 / year

Large course plan
250 upgrades Member hosting
500 upgrades Internet access

$ 999 / 4 months
$ 2499 / year

Frequently asked questions

  • What is the difference between free and paid plans?
    The main differences are increased quotas and the quality of hosting; we also prioritize supporting paying users. We very strongly encourage you to make an account and explore our product for free! There is no difference in functionality between the free and for-pay versions ofCoCalc; everything is still private by default for free users, and you can make as many projects as you want. You can even fully start teaching a course in CoCalc completely for free, then upgrade at any point later so that your students have a much better quality experience (for a small fraction of the cost of their textbook).
  • What does "member hosting" mean?
    There are two types of projects: "free projects" and "member projects". Free projects run on heavily loaded computers. Quite often, these computers will house over 150 simultaneously running projects! Member-hosted projects are moved to much less loaded machine, which are reserved only for paying customers.
    Working in member-hosted projects feels much smoother because commands execute more quickly with lower latency, and CPU, memory and I/O heavy operations run more quickly. Additionally, members only projects are always "ready to start". Free projects that are not used for a few weeks are moved to "cold storage", and it can take a while to move them back onto a free machine when you later start them.
  • What exactly does the quota "internet access" mean?
    Despite the fact that you are accessing CoCalc through the internet, you are actually working in a highly restricted environment. Processes running inside a free project are not allowed to directly access the internet. (We do not allow such access for free users, since when we did, malicious users launched attacks on other computers from CoCalc.) Enable internet access by adding the "internet access" quota.
  • What exactly does the quota "idle timeout" mean?
    By default, free projects stop running after 1 hour of idle time. This makes doing an overnight research computation — e.g., searching for special prime numbers — impossible. With an increased idle timeout, projects are allowed to run longer unattended. Processes might still stop if they use too much memory, crash due to an exception, or if the server they are running on is rebooted. (NOTE: Projects do not normally stop if you are continuously using them, and there are no daily or monthly caps on how much you may use a CoCalc project, even a free one.)
  • What are "CPU shares" and "CPU cores"?
    All projects on a single server share the underlying resources. These quotas determine how CPU resources are shared between projects. Increasing them increases the priority of a project compared to others on the same host computer.
    In particular, "shares" determines the amount of relative CPU time you get.
  • I have a course of 120 students. Which plan should I purchase?
    You can combine and add up course subscriptions! By ordering two times the 'medium course plan', you will get 140 upgrades covering all your students.
  • Do you offer academic discounts?
    Our course subscriptions are for academic use, and are already significantly discounted from the standard plans. Please compare our monthly plans with the 4 month course plans. For example, giving 25 students better member hosting and internet access would require subscribing to 13 "standard plans" for 4 months amounting to $364.
  • There are no CPU/RAM upgrades for courses. Is this enough?
    From our experience, we have found that for the type of computations used in most courses, the free quotas for memory and disk space are plenty. We do strongly suggest the classes upgrade all projects to "members-only" hosting, since this provides much better computers with higher availability.
  • How do I get an invoice with a specific information?
    After purchasing, please email us at [email protected], reference what you bought, and tell us the payer's name, contact information and any other specific instructions. We will then respond with a custom invoice for your purchase that satisfies your unique requirements.
  • Am I required to pay for conducting a course?
    No. You can use all course related functionalities under a free plan.
  • What happens with the files of my students after the course finishes?
    Students will continue to have access to their files after the course, regardless of running the course under a paid plan or for free. Their projects remain accessible, they can (optionally) upgrade their projects with their own subscriptions, and they can also download all files to their local computer.
  • Can I close my web-browser while I'm working?
    Yes! When you close your web-browser, all your processes and running sessions continue running. You can start a computation, shut down your computer, go somewhere else, sign in on another computer, and continue working where you left off. (Note that output from Jupyter notebook computations will be lost, though Sage worksheet output is properly captured.)
    The only reasons why a project or process stops are that it hits its idle timeout, has used too much memory, crashed due to an exception, or the server had to reboot.
  • Which plan offers "private" file storage?
    All our plans (free and paid) host your files privately by default. Please read our Privacy Policy and Copyright Notice.
  • Can I work with Git — including GitHub, Bitbucket, GitLab, etc.?
    Git and various other source control tools are installed and ready to use via the "Terminal". But, in order to also interoperate with sites hosting Git repositories, you have to purchase a plan giving you "internet upgrades" and then applying this upgrade to your project.
  • Are my files backed up?
    All files in every project are snapshotted every 5 minutes. You can browse your snapshots by clicking the "Backups" link to the right of the file listing. Also, CoCalc records the history of all edits you or your collaborators make to most files, and you can browse that history with a slider by clicking on the "History" button (next to save) in files. We care about your data, and also make offsite backups periodically to encrypted USB drives that are not physically connected to the internet.
  • How can I download my project files?
    1. You can download each file individually via the "Files" interface. Select the file and click the "Download" button.
    2. It is also possible to create an archive for a directory or all files. For that, create a "Terminal"-file and issue one of these commands:
      • ZIP archive (Windows): zip -r9 "[filename].zip" [directory-name...]
      • Tarball (Unix-like): tar cjvf "[filename].tar.bz2" [directory-name...]
      (Replace [filename] with the actual filename and [directory-name] by one or more filenames or directory names.) Afterwards, download the archive as explained above.