Connect LinkedIn with a cookie (li_at)

Prosyo normally connects LinkedIn with your email and password in the secure sign-in window. That window has a second option — Cookies — which connects using the session your browser is already signed in with.

Nothing logs in again, so LinkedIn has no reason to send a code, ask for an app approval, or show a security check. Everything after connecting is identical: the same campaigns, the same Inbox sync, the same imports.

When to use this instead of email and password#

What you need#

Before you start#

• Sign in to https://www.linkedin.com in the browser you use every day, on the computer you'll connect from.
• Use a normal window, not private/incognito — an incognito session dies when you close the window, and takes the connection with it.
• Finish anything LinkedIn is showing you there: a security check, confirming your email or phone, a "is this you?" prompt. Copy the cookie only once your feed loads normally.
• Do the copying and the pasting in the same browser on the same computer. LinkedIn ties a session to the browser that created it, and the sign-in window records that browser when you paste.

Find the cookies in your browser#

Chrome, Edge, Brave, Arc, Opera#

1. Open https://www.linkedin.com and make sure you're logged in.
2. Right-click anywhere on the page and choose Inspect, or press F12 (Mac: ⌥⌘I). Developer Tools opens.
3. Open the Application tab along the top. If you can't see it, click the » at the end of the tab strip and pick it from the list.
4. In the left sidebar, under Storage, expand Cookies and click **https://www.linkedin.com**.
5. A table of cookies appears. In the Filter box just above it, type li_at.
6. Click the li_at row. Its full value appears in the panel at the bottom — it's a long string of letters, numbers and symbols, usually 150+ characters.
7. Copy the whole value: right-click the row and choose Copy value, or click into the bottom panel, select everything (Ctrl+A / ⌘A) and copy.
8. Using Sales Navigator or Recruiter? Clear the filter, type li_a, and copy that value the same way.

Firefox#

1. Open https://www.linkedin.com and make sure you're logged in.
2. Press F12 (Mac: ⌥⌘I) to open Developer Tools.
3. Open the Storage tab. If it isn't visible, click » at the end of the tab strip.
4. Expand Cookies in the left sidebar and click **https://www.linkedin.com**.
5. Type li_at in the Filter Items box.
6. Double-click the Value cell of the li_at row to select the whole value, then copy it. You can also right-click the row and choose Copy Value.
7. Repeat with li_a if you use Sales Navigator or Recruiter.

Safari (macOS)#

1. Turn on developer features once: Safari → Settings → Advanced → tick Show features for web developers.
2. Open https://www.linkedin.com and make sure you're logged in.
3. Choose Develop → Show Web Inspector, or press ⌥⌘I.
4. Open the Storage tab, then Cookies in the left sidebar, then linkedin.com.
5. Find the li_at row, double-click its Value, and copy it.
6. Repeat with li_a if you use Sales Navigator or Recruiter.

Paste them into Prosyo#

1. Go to Settings → Accounts.
2. Click the button for what you're doing:
   • Connect LinkedIn — your first LinkedIn account.
   • Connect another LinkedIn — an extra sender, on a plan or seat that allows one.
   • Reconnect LinkedIn — an account showing Needs reconnect.
   • Finish connection — an attempt you started earlier and didn't complete.
3. The secure sign-in window opens. Choose Cookies instead of entering an email and password.
4. Paste your li_at value. Add li_a as well if you use Sales Navigator or Recruiter.
5. Submit. The window closes and the account shows Connecting.
6. Wait for Healthy — usually under a minute. The page refreshes by itself.

Keep the connection alive#

A cookie session lasts for months, but a few actions end it immediately:

When the session ends, the account moves to Needs reconnect, campaigns stop sending from it instead of failing, and you get a notification. Copy a fresh li_at and reconnect the same way.

If it doesn't work#

Agencies and clients#

If you run outreach from a client's LinkedIn account:

• The safest option is to have the client paste their own cookie: give them a teammate seat and this page. See Team seats and invites.
• If they send you the value, use a password manager's secure share or a one-time secret link — never plain email, chat or a screenshot.
• Ask them not to sign out of LinkedIn in that browser afterwards, and to tell you if they change their password.
• One LinkedIn account per seat. Two people should not connect the same LinkedIn account twice in one workspace.

Security#

• li_at is the key to your LinkedIn account for as long as the session lives. Handle it like a password.
• Paste it only into the Prosyo sign-in window that opens from Settings → Accounts. It is served from auth.prosyo.com. If a page anywhere else asks for your LinkedIn cookie, don't paste it.
• To revoke access at any time: LinkedIn → Settings & Privacy → Sign in & security → Where you're signed in → Sign out of all other sessions. Every cookie session, including Prosyo's, stops working straight away.
• Prosyo support will never ask you for a cookie value.

Related#

• Connect LinkedIn — the normal email-and-password route
• Account health and reconnecting — what each status means
• Optimize your LinkedIn profile — before you start sending
• LinkedIn limits explained — safe daily volumes