Good to read all the comments below as my daughter is turning 3 this year and she still puts things in her mouth.
I always thought it was because she hasn’t got all of her back teeth yet and might still have itching or sore gums.

It goes on for quite a while. Probably toddler age, around 2-3 is when mine completely (well, almost completely) stopped. But yours could be earlier and could be later. There is not set timetable with bubbas

3- 4 years…. maybe longer lol

My daughter stopped around 10 months

lol my two year old boy still does it but the girls never really did this lol

simple answer
FOREVER
they never stop not even as kids or teens or adults

While they are teething and cutting teeth they will go this. It is also their way of feeling the texture of things.

i think it will last for a while, but just keep an eye on it

My 19 month old still puts everything in his mouth. This morning he was “tasting” a dead fly he found in a window track. My older daughter stopped fairly young, but I don’t see my 19 month old stopping any time soon lol.

Agree with CURLYTOPS, there is no answer. Your best to start discouraging it now. I still catch my 2 year old putting things she’s not meant to have in her mouth.

My almost three year old still does this ! It drives me nuts!!

mine where all different and my 2 yr old still does

i am hoping asap.. maybe around 18 months?

My “other” child is 43 and still does it…

My 6 month old is the same she puts everything in her
mouth its completely normal

The government nurse that we see says this is normal during a child’s development as they use their tongue to “feel” objects.

Every child is different and so there is no real answer.

Usually around 2-3 years they stop exploring everything with their mouths

I do think its normal – however I think it is generally worse between 9 – 20 months. Our nearly two year old just in the last 6 – 8 weeks stopped putting everything in his mouth.

My daughter is 20 months and still puts everything in her mouth and chews it not sure if it’s her teeth now? Sorry not real helpful I know