I read about someone using a refractometer for antifreeze testing. Are these more accurate than the conventional bulb type gages?

Just use a multi-meter.


1 Like

That’s pretty cool, but it gives you a yes or no test result. I need to also test for freeze temperature point. The refractometer that I’m looking at has freeze temperature and battery level scales. Just wanted to know if this type of measuring is used professionally and accurate.

TRZ 4-in-1 DEF Refractometer Ethylene Glycol, Propylene Glycol in antifreeze Fluids freezing point temperature and freezing point concentration, automotive and industrial battery Fluid

I doubt the refractometer method is more accurate, but easier, less time for clean-up. Only requires 2 or 3 drops of coolant.

I use this to test the freeze point.


plus 1 for the hydrometer. but i have used a Salinity Refractometer for my saltwater fish tank.

Yeah, that’s what I use currently. Completely satisfied with it, but saw these Refractometers and thought if they are dependable I’d switch methods. I’ve been down for health reasons (nothing serious) and got looking for more toys to buy. Just didn’t want to get one if they aren’t dependable. I need accuracy in Northern Michigan. For $20 bucks maybe I’ll just get one as a toy and validate with my other coolant testers.

I always try to avoid purchasing tools for the shop that are fragile.


with a refractometer you have to be careful not to bang it around. you would have zero it out using fresh water and then test with using the antifreeze. at least that’s what I had to do for salinity for my tank.

Sounds easier and more dependable to just keep doing as I do. Thanks all for the input.

1 Like