You can forward ports in your codespace to test and debug your application. You can also manage the port protocol and share the port within your organization or publicly.
Port forwarding gives you access to TCP ports running within your codespace. For example, if you're running a web application on a particular port in your codespace, you can forward that port. This allows you to access the application from the browser on your local machine for testing and debugging.
When an application running inside a codespace prints output to the terminal that contains a localhost URL, such as http://localhost:PORT or http://127.0.0.1:PORT, the port is automatically forwarded. If you're using GitHub Codespaces in the browser or in Visual Studio Code, the URL string in the terminal is converted into a link that you can click to view the web page on your local machine. By default, GitHub Codespaces forwards ports using HTTP.
You can edit the dev container configuration for the repository to automatically forward one or more ports. You can also forward a port manually, label forwarded ports, share forwarded ports with members of your organization, share forwarded ports publicly, and add forwarded ports to the codespace configuration.
Note
Organization owners can restrict the ability to make forward ports available publicly or within the organization. For more information, see Restricting the visibility of forwarded ports.
By default, GitHub Codespaces forwards ports using HTTP but you can update any port to use HTTPS, as needed. If you update a port with public visibility to use HTTPS, the port's visibility will automatically change to private.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port you want to update, then hover over Change Port Protocol.
Select the protocol needed for this port. The protocol that you select will be remembered for this port for the lifetime of the codespace.
You can only make a port private to an organization if your organization uses GitHub Team or GitHub Enterprise Cloud.
If you want to share a forwarded port with others, you can either make the port private to your organization or make the port public. After you make a port private to your organization, anyone in the organization with the port's URL can view the running application. After you make a port public, anyone who knows the URL and port number can view the running application without needing to authenticate.
When you forward a port, your application becomes available at the URL https://CODESPACENAME-PORT.app.github.dev. For example, https://monalisa-hot-potato-vrpqrxxrx7x2rxx-4000.app.github.dev. If you forward a private port from the VS Code desktop application, your application will also be available at a localhost port such as 127.0.0.1:4000.
To access your application using a REST client, such as Postman, or a command-line tool like curl, you don't need to authenticate if you're using a localhost port, or if you're accessing a public port at the remote domain. However, to connect to a private port at the remote domain, you must authenticate by using the GITHUB_TOKEN access token in your request.
Note
The GITHUB_TOKEN is automatically created when you start a codespace and remains the same for the duration of the codespace session. If you stop and then restart a codespace a new GITHUB_TOKEN is generated.
You can add a forwarded port to the GitHub Codespaces configuration for the repository, so that the port will be automatically forwarded for all codespaces created from the repository. After you update the configuration, any previously created codespaces must be rebuilt for the change to apply. For more information about the dev container configuration file, see Introduction to dev containers.
In your codespace, open the dev container configuration file you want to update. Typically this file is .devcontainer/devcontainer.json.
Add the forwardPorts property.
"forwardPorts":[NUMBER],
Replace NUMBER with the port number you want to forward. This can be a comma-separated list of port numbers.
When you open a codespace in the browser, or in the VS Code desktop application, you can label a forwarded port to make it easier to identify in a list.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port you want to label, then click Set Port Label.
You can label a port and write the change to a dev container configuration file for the repository. If you do this for a port that is automatically forwarded, using the forwardPorts property, then the label will be automatically applied to that forwarded port for all future codespaces created from the repository using that configuration file.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port whose label attribute you want to add to the codespace configuration, then click Set Label and Update devcontainer.json.
Type a label for your port, then press Enter.
If your repository has more than one dev container configuration file, you will be prompted to choose which file you want to update.
The dev container configuration file is updated to include the new label in the portsAttributes property. For example:
// Use 'forwardPorts' to make a list of ports inside the container available locally."forwardPorts":[3333,4444],"portsAttributes":{"3333":{"label":"app-standard-preview"},"4444":{"label":"app-pro-preview"}}
When an application running inside a codespace prints output to the terminal that contains a localhost URL, such as http://localhost:PORT or http://127.0.0.1:PORT, the port is automatically forwarded. If you're using GitHub Codespaces in the browser or in Visual Studio Code, the URL string in the terminal is converted into a link that you can click to view the web page on your local machine. By default, GitHub Codespaces forwards ports using HTTP.
You can edit the dev container configuration for the repository to automatically forward one or more ports. You can also forward a port manually, label forwarded ports, share forwarded ports with members of your organization, share forwarded ports publicly, and add forwarded ports to the codespace configuration.
Note
Organization owners can restrict the ability to make forward ports available publicly or within the organization. For more information, see Restricting the visibility of forwarded ports.
You can only make a port private to an organization if your organization uses GitHub Team or GitHub Enterprise Cloud.
If you want to share a forwarded port with others, you can either make the port private to your organization or make the port public. After you make a port private to your organization, anyone in the organization with the port's URL can view the running application. After you make a port public, anyone who knows the URL and port number can view the running application without needing to authenticate.
When you forward a port, your application becomes available at the URL https://CODESPACENAME-PORT.app.github.dev. For example, https://monalisa-hot-potato-vrpqrxxrx7x2rxx-4000.app.github.dev. If you forward a private port from the VS Code desktop application, your application will also be available at a localhost port such as 127.0.0.1:4000.
To access your application using a REST client, such as Postman, or a command-line tool like curl, you don't need to authenticate if you're using a localhost port, or if you're accessing a public port at the remote domain. However, to connect to a private port at the remote domain, you must authenticate by using the GITHUB_TOKEN access token in your request.
Note
The GITHUB_TOKEN is automatically created when you start a codespace and remains the same for the duration of the codespace session. If you stop and then restart a codespace a new GITHUB_TOKEN is generated.
You can add a forwarded port to the GitHub Codespaces configuration for the repository, so that the port will be automatically forwarded for all codespaces created from the repository. After you update the configuration, any previously created codespaces must be rebuilt for the change to apply. For more information about the dev container configuration file, see Introduction to dev containers.
In your codespace, open the dev container configuration file you want to update. Typically this file is .devcontainer/devcontainer.json.
Add the forwardPorts property.
"forwardPorts":[NUMBER],
Replace NUMBER with the port number you want to forward. This can be a comma-separated list of port numbers.
When you open a codespace in the browser, or in the VS Code desktop application, you can label a forwarded port to make it easier to identify in a list.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port you want to label, then click Set Port Label.
You can label a port and write the change to a dev container configuration file for the repository. If you do this for a port that is automatically forwarded, using the forwardPorts property, then the label will be automatically applied to that forwarded port for all future codespaces created from the repository using that configuration file.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port whose label attribute you want to add to the codespace configuration, then click Set Label and Update devcontainer.json.
Type a label for your port, then press Enter.
If your repository has more than one dev container configuration file, you will be prompted to choose which file you want to update.
The dev container configuration file is updated to include the new label in the portsAttributes property. For example:
// Use 'forwardPorts' to make a list of ports inside the container available locally."forwardPorts":[3333,4444],"portsAttributes":{"3333":{"label":"app-standard-preview"},"4444":{"label":"app-pro-preview"}}
To forward a port use the gh codespace ports forward subcommand. Replace codespace-port:local-port with the remote and local ports that you want to connect. After entering the command choose from the list of codespaces that's displayed.
You can only make a port private to an organization if your organization uses GitHub Team or GitHub Enterprise Cloud.
If you want to share a forwarded port with others, you can either make the port private to your organization or make the port public. After you make a port private to your organization, anyone in the organization with the port's URL can view the running application. After you make a port public, anyone who knows the URL and port number can view the running application without needing to authenticate.
To change the visibility of a forwarded port, use the gh codespace ports visibility subcommand. There are three visibility settings:
private - Visible only to you. This is the default setting when you forward a port.
org - Visible to members of the organization that owns the repository.
public - Visible to anyone who knows the URL and port number.
Replace codespace-port with the forwarded port number. Replace setting with private, org, or public. After entering the command choose from the list of codespaces that's displayed.
When you forward a port, your application becomes available at the URL https://CODESPACENAME-PORT.app.github.dev. For example, https://monalisa-hot-potato-vrpqrxxrx7x2rxx-4000.app.github.dev. If you forward a private port from the VS Code desktop application, your application will also be available at a localhost port such as 127.0.0.1:4000.
To access your application using a REST client, such as Postman, or a command-line tool like curl, you don't need to authenticate if you're using a localhost port, or if you're accessing a public port at the remote domain. However, to connect to a private port at the remote domain, you must authenticate by using the GITHUB_TOKEN access token in your request.
Note
The GITHUB_TOKEN is automatically created when you start a codespace and remains the same for the duration of the codespace session. If you stop and then restart a codespace a new GITHUB_TOKEN is generated.
To find the address for a forwarded port, enter gh codespace ports. If you have more than one codespace, select the appropriate codespace from the list that's displayed.
Copy the address and paste it somewhere for later use.
You can add a forwarded port to the GitHub Codespaces configuration for the repository, so that the port will be automatically forwarded for all codespaces created from the repository. After you update the configuration, any previously created codespaces must be rebuilt for the change to apply. For more information about the dev container configuration file, see Introduction to dev containers.
In your codespace, open the dev container configuration file you want to update. Typically this file is .devcontainer/devcontainer.json.
Add the forwardPorts property.
"forwardPorts":[NUMBER],
Replace NUMBER with the port number you want to forward. This can be a comma-separated list of port numbers.
When you open a codespace in the browser, or in the VS Code desktop application, you can label a forwarded port to make it easier to identify in a list.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port you want to label, then click Set Port Label.
You can label a port and write the change to a dev container configuration file for the repository. If you do this for a port that is automatically forwarded, using the forwardPorts property, then the label will be automatically applied to that forwarded port for all future codespaces created from the repository using that configuration file.
Open the terminal in your codespace.
Click the PORTS tab.
Right-click the port whose label attribute you want to add to the codespace configuration, then click Set Label and Update devcontainer.json.
Type a label for your port, then press Enter.
If your repository has more than one dev container configuration file, you will be prompted to choose which file you want to update.
The dev container configuration file is updated to include the new label in the portsAttributes property. For example:
// Use 'forwardPorts' to make a list of ports inside the container available locally."forwardPorts":[3333,4444],"portsAttributes":{"3333":{"label":"app-standard-preview"},"4444":{"label":"app-pro-preview"}}
You can see the port labels when you list the forwarded ports for a codespace. To do this, use the gh codespace ports command and then select a codespace.