Curtain rail 230cm - how wide should my curtains be?

[NewHouseNoMoney]

Advice online differs - should they be 1.5x the width or 2x the width?

Depends on type of heading really, I would always go for double width for fullness. If readymade curtains then 90" wide.

It depends how gathered you want them to be. I'm assuming you're going for pencil pleats. 2x if you want then really gathered and invited at the edge of the window, 1.5x otherwise.

obvious, not invited!

2x it is, thank you!

Each curtain should be about the width of the rail - so you are after a pair of curtains, each around 230m wide. As above if ready made, you are looking at 90 inches.