Can't ever go wrong with the classical approach and play the Queens Gambit declined.
Openings for Black Similar to Catalan

Didn't read your question just the title. How about the Gruenfeld. A lot of material on this opening and its a fun one for black


Uhm, the most similar opening to the Catalan is the Catalan!
You cannot force White to play the same as what you play as White.
The Catalan is reached via 1.d4 d5 2.c4 e6 3.Nf3 Nf6 4.g3 OR 1.d4 Nf6 2.c4 e6 3.g3.
So if you truly understand the Catalan, then the way to get there on the Black side is via 1...Nf6 and 2...e6 OR 1...d5 and 2...e6.
Which you should play depends on which other openings you are willing to learn.
If you go the 1...d5 and 2...e6 route, you need to learn 3.Nc3, the main line of the QGD. You'd have to study the Exchange Variation and one of Lasker, Tartakower, or Orthodox. Otherwise, you could learn the Tarrasch Defense.
If you take the 1...Nf6/2...e6 route, you would need something against 3.Nc3 (Nimzo-Indian or QGD) and something against 3.Nf3 (QGD, Queen's Indian, Bogo-Indian, or Modern Benoni).
It is just like how you cannot force the catalan as White and need something for the KID, Grunfeld, Benoni, Slav, Semi-Slav, and QGA.
It is just like how you cannot force the catalan as White and need something for the KID, Grunfeld, Benoni, Slav, Semi-Slav, and QGA.
Yeah I don't mean I want to play the catalan as black, I just want an opening to play as black that is a similar style to playing the catalan as white. Basically want something where you get active and dynamic pieces without it being a race to checkmate like in the KID.
Grunfeld seems to be the most popular suggestion, so I'll make sure to check it out. My main worry is that it has a ton of theory and forcing lines, but it's probably not as bad as the modern benoni in terms of messing up one move and immediately losing.
Anyone know the difference between the Grunfeld and Neo Grunfeld? Or is it just based on white's setup?

Anyone know the difference between the Grunfeld and Neo Grunfeld? Or is it just based on white's setup?
In the main-line Gruenfeld, White plays an early Nc3 (typically on move 3. Nc3, right after 1. d4 and 2. c4). That allows Black to trade Knights on c3 when his d5-Knight is kicked by e2-e4.
In the Neo-Gruenfeld, White defers Nc3, so that Black cannot exchange Knights on c3 in reply to e2-e4... and must retreat his d5-Knight instead. THEN White plays Nc3.
I like playing the Catalan as White, and I'm trying to figure out what opening I should play against 1. d4 from the black side of things. Basically looking for something fairly positional where you get good active pieces.
Maybe benko gambit is similar in that you gambit a pawn to gain space on the queenside (I'm just not sure how objectively strong it is, and anti benonis are so common). Nimzo indian is also maybe an option it just seems too tragic to trade off a bishop so early.