Number of gem sockets in Uniques

Hello, I'm new to this game and I have a question about the number of gem sockets a unique item can have. To my knowledge the number of sockets depends on the item level of the item. So if I find a unique with itemlevel 17 I would assume it can only have 3 sockets. I tried using ~20 jewelers orbs on it but it wouldn't go over 3 sockets. While someone else might find the same unique with at a higher item level so it supports 5 or 6 sockets.

So it's basically the same item with the same stats, but the itemlevel 17 one is limited to 3 sockets? Or can I also get 4/5/6 sockets on the itemlevel 17 unique?

This is kinda confusing when buying a unique because you dont really see what itemlevel it has and usually you want more than 3 sockets in such an amazing item.

Uniques works the same way as any other item; the number of sockets depend on the ilvl.

1 socket : 1
2 sockets: 1
3 sockets: 15
4 sockets: 28
5 sockets: 35
6 sockets: 50

Thank you for your answer. It makes me sad though that my Searing Touch unique staff can only have 3 Sockets :(

While there are other ST staffs out there that actually might even have inferior stats but can have more sockets because an invisible internal number is higher.

Yea I don't know why ilvl is hidden, hopefully they will add it to the item description so that you don't need /itemlevel.

I have a level 17 chest armor that I found in a level 51 area with 5 sockets on it. Maybe items you find don't have a socket limit relative to level. Maybe the socket limit only applies for items you personally attempt to modify.