Consider getting thread gauges or making your own by gluing/welding standard size bolts to little sticks/rods with clear labels on them. A thread gauge will typically have a go/no-go but even a simple one can be a useful shop tool.
Just go to Lowes and buy one of each bolt along with some dowels.. the easy way is to drill a hole in the dowel, cut the head off the bolt and glue it into place. HIgher quality would be brazing or welding them to little rods with knurling or something.
Or MCMASTER.
You can also kinda use taps but if its close but no cigar you might damage the thread with a sharp tap. A bolt will simply get stuck.
Good enough for chassis work (but if your doing screw terminals or electrical contacts you should get real thread gauges). These have a benefit because they are extremely cheap and you can make them long/skinny if you select the right dowel, so you can get it deep into a chassis hole some where (you won't have a problem making one thats a foot long with a 1/4 inch dowel). The machine shop ones are kinda stubby usually. And since they are double sided, its not super ergonomic because you end up being poked by a screw thread when you install it (not like a real handle)
Gluing a thread into a dowel, giving it a bit of lacquer, putting a label on it and then covering with clear heat shrink will make something pretty nice and very cheap
Another option that won't really work too well but will kinda work in a pinch is to get bolt samples and put them in one of those screw drivers that has some of those holding pincers on it meant for screw insertion.
https://content.artofmanliness.com/uploads//2010/02/screwholder.jpg