This wikiHow teaches you how to look up someone else's user identification number or (user ID) on Facebook.
Step
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Step 1. Launch a web browser and visit
To find a user ID, you must use your computer's web browser.
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Step 2. Sign in to Facebook
Type your username and password into the empty fields in the upper right corner, then click Login.
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Step 3. Visit the desired person's profile
To search for them, type the person's name into the search field at the top of the screen or click their name in your friends list.
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Step 4. Right-click the gray area on the person's page
This gray area is to the right and left of the person's profile. If you click on it, it will bring up a short menu.
If your mouse doesn't have a right-click button, press Ctrl on your keyboard while you left-click the mouse
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Step 5. Click View page source
This will open a new tab showing the source code for the page.
If " View page source " does not appear, look for other similar options, such as " View source " or " Page source"
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Step 6. Press Ctrl+F (on Windows) or Command+F (for macOS).
This will bring up a search box.
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Step 7. Type profile_id in the search box, then press Enter (on Windows) or Return (on macOS).
The user ID of the person you are looking for will be displayed to the right of " profile_id ".