How to run multiple instances of Claude Desktop on a Mac

Why a second instance needs its own data folder

Claude Desktop stores its sign-in, chats and settings in a data folder in your user Library. If you simply open the app again, macOS brings the running copy to the front instead of starting a new one. Even if you forced a second copy to start with the same folder, it would see the same account.

The workaround tells the second copy to use a different folder. With its own folder, the second copy starts signed out, and you can sign in to a different account there while the first copy keeps running.

The command people use

The commonly shared method is a Terminal command like this one:

open -n -a "Claude" --args --user-data-dir="$HOME/Library/Application Support/Claude-Work"

Here is what each part does:

open -n asks macOS to open a new instance of the app even if one is already running.
-a "Claude" names the app.
--args passes everything after it to the app itself.
--user-data-dir=... points that copy at a separate folder. Use a different folder name for each account.

Because this is not an Anthropic feature, it can stop working after an update without notice. Anthropic's supported setup is the standard install described in Install Claude Desktop, which ends with signing in with your account.

What goes wrong

Both copies look the same. Each instance has the same app name and the same Dock icon. With two or three running, you have to open each window to find out which account it is.
Sign-in lands in the wrong window. Claude finishes sign-in in your browser, and the browser hands it back to whichever Claude window macOS picks, often the copy that was already open. Your second account can end up in the first copy. Why this happens and how to fix it.
You redo it every time. The command only lasts for that launch. After a restart or a quit, you run it again, from Terminal or a script you keep somewhere.
No direct way to jump to an account. Command–Tab shows one Claude icon per copy, all identical, so there is nothing to tell them apart.

Making the manual method easier to live with

If you stay with the workaround, a few habits help:

Give each data folder a clear name, such as Claude-Work and Claude-Personal, and never reuse one for a different account.
Save each command in a small script so you don't retype paths.
Sign in to a new copy while no other copy is running, so the browser has only one window to hand sign-in back to.
Check the account name in the window before you paste anything sensitive.

How a profile manager avoids the problems

Switch does the same basic thing in a more permanent way. Each profile opens Anthropic's own Claude Desktop app, unmodified, pointed at its own data folder. Switch checks Claude's signature before launching it and never patches, re-signs or wraps the app.

The difference is what surrounds each copy. Every profile has a name, one of 16 colors and its own colored Dock icon, so you can see which account is which. Each profile can have a global keyboard shortcut that works from any app while Switch is running. Profiles stay set up between restarts, and one click tiles every open profile side by side, each outlined in its color. See Claude Desktop profiles for Mac for the details.

What extra instances don't change

One thing doesn't change with any of these methods: each account keeps its own plan and its own usage limits. Running several accounts is for keeping separate work apart, not for getting more usage. Rotating accounts to get around limits can conflict with Anthropic's terms.

Each instance also uses memory like any other copy of Claude Desktop, so quit the ones you aren't using. For a wider comparison of methods, read Claude Desktop with multiple accounts.