How to find wallet version from old wallet.dat?

How can I find out the core wallet version for an old wallet.dat file? I got some backups and wanna make sure I'm using the right version before loading it up.

You really should be careful with those old wallet.dat files. Did you get them from somewhere specific? It's important to be upfront about it so you don't end up with issues later on. Make sure you have a clean copy of the wallet.dat that hasn’t been opened in any newer clients. I’d recommend keeping the original safe and only using a copy to avoid any problems. Then, to check the version: load your copy of the wallet.dat file, and once it’s done loading, look for the "debug.log" file. There you’ll see a line that shows the wallet loading process, which should tell you the version you’re dealing with.