Our four were around 18months to 2 years. Around that age they’d start trying to climb out on their own and wanting to sit with everyone. We could remove the tray on our high chair and adjust the height so it sat just under the dining room table like a big chair, so they did use it quite a bit longer like that. We also tried a firm pillow on a chair once they were about 2 and just wanted to join in at the table like the rest of the family.

When they decided the high chair was for babies! I think around 15 months.

yeah around a year. we bought a special seat for them to sit in that just goes over a normal chair, like a booster thing but they sit in it, not on it.

All 3 of mine were between 18 months and 2 years (or when they started to clim out!) We have a Toosh Coosh on a dining chair that our youngest has used since whe was almost 2 (he’s now 4)

About 18 months old but it depends on how high your chairs are