Roblox ID
Watch the video: How to find a Roblox ID1
Open the profile
Go to the Roblox profile of the user.
2
Read the URL
The number in the link is the ID: roblox.com/users/123456789/profile
Discord ID
Watch the video: How to find a Discord ID1
Enable Developer Mode
Discord: Settings, Advanced, Developer Mode on.
2
Copy the ID
Right-click the user (or your own name) and choose Copy User ID.