Q&A for How to Know if Someone Is Online

It depends on whether you're friends with this person or not. If you are you should check for a green dot next to their profile.

You can change your status to "offline" and see if that works, but it depends on the actual messaging service.

Click the magnifying glass icon (search) and type in the username. When the profile comes up, click on it and click Message. You don't have to send a message; if there is a green dot on the user's profile photo, the person is online. If not, it will list the last time the user was online.

That usually means the person is online. On most sites the dot is green, but on other sites, it could be another color. To test it, log in to your account, and open an incognito window or another browser where you are not logged in. If you see a blue dot, that means you are online.