Follow all three of the following steps to download, register, and install CotranslatorAI Free on your computer:

Step 1: Get CotranslatorAI Free

A. Download CotranslatorAI Free

Download the CotranslatorAI Free 64-bit version for Windows from the link/button below:

SPECIAL NOTE TO EXISTING USERS: If you have previously installed CotranslatorAI or CotranslatorAI Free and are here only to update to the latest version, then you do not need to continue to Step 2 below. Simply download the latest version from the link above and follow the installation instructions. Your CotranslatorAI registration code, OpenAI API key, and prompts in your Prompt Library will all remain intact and be ready to use after installation.

Also be sure to check our resources below:

B. Install CotranslatorAI

Follow these steps to install CotranslatorAI Free:

  1. Install CotranslatorAI Free using the installation program. (If you are in a corporate environment, the installation program does not require administrator rights for installation, so you must be logged in using your personal Windows user account that you use for your work.)
  2. Read and accept the license agreement.
  3. On the next page of the installation program, choose the location for the CotranslatorAI Free program and data files. By default, CotranslatorAI Free is installed to the Documents folder of the current Windows user (C:\Users\username\Documents\CotranslatorAI). We recommend that you install in the default folder. However, you can change this location to another folder (e.g. C:\Users\username\CotranslatorAI). If you decide to install the program in a folder outside your user folder (C:\Users\username), please make sure that this folder can be written to when you use CotranslatorAI Free. This is necessary for updating prompt files and configuration files located in the CotranslatorAI Free program folder.
  4. On the next page of the installation program, click the Install button.
  5. CotranslatorAI Free requires .NET Desktop Runtime v.6 from Microsoft. If this runtime is not yet installed on your computer, the installation program will automatically download the installation file for .NET Desktop Runtime v.6, so an internet connection is required. When the downloading completes, .NET Desktop Runtime v.6 installation program will be run. Follow the prompts to install it. When installation completes, CotranslatorAI Free’s installation program will resume and complete the installation process.
  6. On the last page of the installation program, you will be prompted to launch CotranslatorAI Free. You can check the box to run it immediately, or select CotranslatorAI Free from the Windows start menu later.
  7. In addition to the main CotranslatorAI Free application, the installation program also installs the CotranslatorAI Companion application. This is a small application responsible for processing keyboard shortcuts in order to run your keyboard shortcuts assigned to prompts in the prompt library and which also enables you to use the keyboard shortcuts assigned to built-in commands in order to use CotranslatorAI Free more efficiently. CotranslatorAI Companion is configured to start every time Windows starts up and is automatically started after installation. CotranslatorAI Companion can be accessed from the Windows system tray (indicated by the up” arrow in the task panel next to the system clock, in the bottom right corner of the screen). More information about CotranslatorAI Companion can be found in the User Guide.

Step 2: Get and enter your CotranslatorAI Free registration code

A. Register CotranslatorAI Free

Fill out the registration form below, select the Email checkbox, and then click the Register button to receive your CotranslatorAI Free registration code.

CotranslatorAI Registration Form

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Please select the Email checkbox below so we can email you your personal registration code and put you on our email list for updates on CotranslatorAI and other tips on using AI in your work.

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B. Get your CotranslatorAI Free registration code

After filling out the form above, you will receive an email to confirm your email address. Click the confirmation link and prove that you are human. You will then receive another email containing your CotranslatorAI Free registration code within 5-10 minutes. If you don’t see the email, be sure to check your spam folder!

C. Enter your CotranslatorAI Free registration code in CotranslatorAI Free

  1. Launch CotranslatorAI Free and activate it by clicking I have a registration code button. (If you did not complete the registration process in Step 2A above, click the Register for free button to do so.)
    Register for free
  2. Enter your CotranslatorAI Free registration code. You may use this CotranslatorAI Free registration code on all of your devices. In a corporate environment, please ensure that each employee receives a separate code.
  3. Click the Register button.
  4. You will now be prompted to change the OpenAI API key in the CotranslatorAI Free configuration dialogue.

    You can click the Yes button to open the Configuration Dialogue window so that it will be ready for you in Step 3. Or you can click the No button to close out and then proceed immediately with Step 3 anyway, or come back to Step 3 later.

Step 3: Get and enter your OpenAI API key

A. Set up a developer account with OpenAI

To use CotranslatorAI Free, you will need an OpenAI API key. To obtain this key, you need to create a so-called “developer” account on the OpenAI platform at (IMPORTANT: This is not the same as a ChatGPT/ChatGPT+ account at!) Create your developer account by clicking the Sign up link. After you sign up, you will be given a small balance of free credit that can be used during a short trial period (three months at the time of writing). After the trial period ends or the free credit is used up, you will need to provide your credit card details in your OpenAI developer account in the menu under your username at the top-right of the screen (Billing > Payment Methods). To avoid this hassle later, you can also enter your credit card details now, and even set up usage limits to control your costs.

B. Enter your OpenAI key in the CotranslatorAI Free configuration dialogue

  1. To get an OpenAI API key from your account on the OpenAI platform (, click your username at the top-right of the screen and select the View API Keys menu item.
  2. Click the Create new secret key button and a panel will be displayed asking for a name for your OpenAI API key (referred to on this panel as a “secret key”). You can assign a name to the new OpenAI API key if you wish (it is optional) and then click the Create secret key button on the panel. A new OpenAI API key will be generated for you.
  3. Click the button next to the OpenAI API key (the graphic in the button looks like two overlapping boxes) to copy it to the clipboard. Note that the OpenAI API key will no longer be accessible once you click the Done button, and the shortened OpenAI API keys which you see in the list of keys may not be used again. However, if you forget to copy the full OpenAI API key before closing this panel, if you you lose an OpenAI API key, or just wish to change your OpenAI API key, you can always generate a new one on this page. Also, if you think that your OpenAI API key could be or could have been seen by someone else, you can disable it by clicking the trash icon next to the OpenAI API key and then creating a new one and copying it to CotranslatorAI Free.
  4. Now that you have your OpenAI API key, go to the configuration dialogue that you opened at the end of Step 2, or open it now in CotranslatorAI Free from the Tools > Options menu.
  5. Select the OpenAI API tab, click the Update button, paste your OpenAI API key from the clipboard and click OK.
  6. In future versions, the OpenAI API key will be encrypted. But for now it is available as plain text, so make sure not to share your CotranslatorAI Free configuration file with others.

Now you are all set to use CotranslatorAI Free!