So the gym I train at (they grabbed me after I saw my kids doing it) has a rule that they need to be at least 3 and potty trained, so our youngest started a little bit ago and is more working on the skill of listening and paying attention than some of the techniques but my 5 yo is learning some good stuff and is soon going to move from the young children's class to the youth class where the emphasis moves from holding still and paying attention to actual BJJ.
So I'd say 4 is a good age to start, if you need to find a good gym I'd recommend going over to old.reddit.com/r/bjj and asking for advice on there, you'll probably get some good advice.
Also it makes wrestling with the kids way more fun when they try and practice their BJJ at the same time.
Great thanks for the feedback and resources! This led me down a path to discover we have a dojo in our neighborhood I was unaware of and they have an age 3-5 class. Just in time for winter break too! Thanks again- I would have just assumed he was too young for BJJ but this is pretty exciting actually. I probably won't do it myself but he can practice on me at home :)
So I'd say 4 is a good age to start, if you need to find a good gym I'd recommend going over to old.reddit.com/r/bjj and asking for advice on there, you'll probably get some good advice.
Also it makes wrestling with the kids way more fun when they try and practice their BJJ at the same time.