The sound I’m thinking of isn’t so much a snort, it’s not expelled from the nose, however, a sound used to express humor or amusement that doesn’t quite hit the laughter threshold. I notice I do it and was trying to use it in writing. Normally it’s a “T” sound or sometimes an “heh” as I expell a forceful puff of air. Usually I notice my tongue is pushed against the back of my upper front teeth, not touching my palate but don’t know if that differs for people and it’s more the action of air expulsion than type of sound?
Hopefully this makes sense, I’ve had issues here with people being mean on this site with legitmate questions so I hope I covered bases ok. Looking for a name for this or anything else relevent to it for descriptive purposes. Or is there a more universally accepted way to spell out the sounds that are lumped with this? I appreciate any insight!
I suggest the onomatopoeic titter. Lexico has
[Give] a short, half-suppressed laugh
While reading, I ranged from smiles to titters to outright belly laughs.