Claude User Guide: From Sign-Up and Login to Email Linking and Multi-Account Switching

This tutorial covers only the basics of using Claude: how to sign up, log in, switch accounts on the same device, and the details to watch out for when syncing across multiple devices. Follow the steps below to straighten out issues like “can’t get in,” “can’t switch accounts,” and “history not syncing” all at once.

I. Claude registration and first-time login process

Open the official Claude website (claude.ai). After clicking the login/sign-up entry, the page usually offers two methods: email login or third-party account login. When choosing email login, Claude will generally send a one-time login link to your email; go back to your inbox and click it to complete the login.

In some regions, registering for Claude may involve additional verification steps (such as SMS or other checks). Just follow the on-page instructions to complete them. If you don’t receive the email, first check your spam folder or your corporate email filtering rules, or try again with a commonly used personal email address.

II. The “linking” idea for login methods: stick to one entry point as much as possible

Many people feel their Claude “accounts are a mess,” but the issue is often caused by mixing login methods: the same email may have been used both with an email magic link and with a third-party login, making you think it’s the same account when in fact you’ve entered different Claude spaces under different identities.

A more reliable approach is to pick one long-term login entry (either email or a third party) and then always use that same method to access Claude. If you need to change your email, first confirm whether the chat history from the old and new accounts needs to be migrated (in most cases, chat histories will not be merged automatically).

III. The right way to switch Claude accounts (same device / multiple browsers)

To switch Claude accounts on the same computer, the cleanest method is to log out in Claude first and then log in with another account. Simply “closing the tab” often won’t clear the session, which can make it seem like you switched accounts when you’re actually still in the original one.

If you need to stay logged into two Claude accounts at the same time, it’s recommended to use different browsers to log in separately, or use an incognito window / separate browser profiles. This helps prevent cookies from overwriting each other and reduces the chance of mixing up history and file uploads.

IV. Syncing and common sticking points: missing history, repeated login redirects

Claude’s chat history is usually tied to the account: logging into the same account on multiple devices will sync, while switching accounts will show different history lists. If you find that “history is missing,” first verify whether Claude is currently using the same login method you used originally (email login or third-party login).

If you run into issues like repeated login redirects or a blank page, you can first clear the site’s cache and cookies and then log into Claude again, or temporarily switch to another browser to test. An unstable network environment can also cause verification emails or redirect callbacks to fail; it’s recommended to complete registration and the first login on the same network before starting regular day-to-day use of Claude.