> For the complete documentation index, see [llms.txt](https://calctree.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://calctree.gitbook.io/docs/desktop-app.md).

# Desktop app

Use CalcTree on Windows, connect your pages to the engineering software running on your machine, and let CalcTree AI work with it.

The CalcTree desktop app is CalcTree for Windows. It is the same editor you use in the browser, with the same workspaces, pages, templates and collaborators. What it adds is **connections**: your calculations, and CalcTree AI, can work directly with the engineering software open on your computer.

## What you can do with it

* **Everything you do in the web app.** Write calculations, run Python, use templates, review pages and collaborate. Your work is saved to your CalcTree workspace exactly as it is in the browser.
* **Bring your analysis software into your calculations.** Read data from an open model or file, such as a table of results or a range of cells, into page variables. Use it in your calculations, checks and reports, and write values back into the model or file.
* **Let CalcTree AI drive your software.** Once connections are on for your workspace, CalcTree AI can look at the files you have open, set up connections for you, and help you build calculations and reports from the data in your tools.
* **Script the software directly.** Each connection has a Python script block for anything a simple mapping can't do, such as picking one value out of a large table.
* **Re-run with one click.** When the model or file changes, run the sync again and every calculation on the page updates.

See [Connections](/docs/desktop-app/connections.md) for how they work and which software you can connect to.

## Requirements

* A 64-bit Windows computer.
* An internet connection. The desktop app works with your online CalcTree workspace, so it does not work offline.
* A CalcTree account. The desktop app is included on every plan, including free.
* For connections: the software you want to connect to, installed and running on the same computer.

{% hint style="info" %}
The desktop app is Windows only. There is no macOS version.
{% endhint %}

## Download

Both links always give you the current release.

| Download                                                                              | Use it when                                                           |
| ------------------------------------------------------------------------------------- | --------------------------------------------------------------------- |
| [CalcTree-Setup.exe](https://d30fdxlqv0ec94.cloudfront.net/latest/CalcTree-Setup.exe) | You are installing on your own computer. Recommended for most people. |
| [CalcTree.msi](https://d30fdxlqv0ec94.cloudfront.net/latest/CalcTree.msi)             | Your IT team deploys software to many machines.                       |

{% hint style="info" %}
This is an early release. We are still improving it, so if something doesn't work as you expect, let us know.
{% endhint %}

## Install and sign in

{% stepper %}
{% step %}

### Run the installer

Open the `CalcTree-Setup.exe` file you downloaded and follow the prompts. You can install it just for yourself or for everyone on the computer.
{% endstep %}

{% step %}

### Open CalcTree

Start **CalcTree** from the Start menu.
{% endstep %}

{% step %}

### Sign in

Sign in with your CalcTree email address and password. The app opens the workspace you last used. If you don't have an account yet, choose **Sign up**.
{% endstep %}
{% endstepper %}

If Windows warns you about the installer, see [Troubleshooting](/docs/desktop-app/troubleshooting.md).

## Updating

To update, download again from this page and run the installer over your existing install. The download links always point at the current release, and your pages and settings live in your workspace, so nothing is lost.

## Desktop app or web app?

Use whichever you like for everyday work: pages are the same in both. You need the desktop app only to **set up or run a connection**, or to have CalcTree AI work with your local software. In the web app, a connection shows the values from its last sync as read-only, so colleagues without the desktop app can still read and review the page.

The desktop app opens at 80% zoom. Use **Ctrl +**, **Ctrl -** and **Ctrl 0** to change it.