content/authentication/connecting-to-github-with-ssh/checking-for-existing-ssh-keys.md

---
title: Checking for existing SSH keys
intro: 'Before you generate an SSH key, you can check to see if you have any existing SSH keys.'
redirect_from:
  - /articles/checking-for-existing-ssh-keys
  - /github/authenticating-to-github/checking-for-existing-ssh-keys
  - /github/authenticating-to-github/connecting-to-github-with-ssh/checking-for-existing-ssh-keys
versions:
  fpt: '*'
  ghes: '*'
  ghec: '*'
topics:
  - SSH
shortTitle: Check for existing SSH key
---

## About SSH keys

You can use SSH to perform Git operations in repositories. For more information, see [AUTOTITLE](/authentication/connecting-to-github-with-ssh/about-ssh).

If you have an existing SSH key, you can use the key to authenticate Git operations over SSH.

## Checking for existing SSH keys

Before you generate a new SSH key, you should check your local machine for existing keys.

{% data reusables.ssh.key-type-support %}

{% data reusables.command_line.open_the_multi_os_terminal %}
1. Enter `ls -al ~/.ssh` to see if existing SSH keys are present.

   ```shell
   $ ls -al ~/.ssh
   # Lists the files in your .ssh directory, if they exist
   ```

1. Check the directory listing to see if you already have a public SSH key. By default, the filenames of supported public keys for {% data variables.product.github %} are one of the following.
   * _id_rsa.pub_
   * _id_ecdsa.pub_
   * _id_ed25519.pub_

   > [!TIP]
   > If you receive an error that _~/.ssh_ doesn't exist, you do not have an existing SSH key pair in the default location. You can create a new SSH key pair in the next step.

1. Either generate a new SSH key or upload an existing key.
   * If you don't have a supported public and private key pair, or don't wish to use any that are available, generate a new SSH key.
   * If you see an existing public and private key pair listed (for example, _id_rsa.pub_ and _id_rsa_) that you would like to use to connect to {% data variables.product.github %}, you can add the key to the ssh-agent.

     For more information about generation of a new SSH key or addition of an existing key to the ssh-agent, see [AUTOTITLE](/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent).