Your mask fit determines everything.

Yes, fog prevention matters, but if the mask doesn’t fit your face, nothing else will help. Comfort comes second, but if it leaks, you’ll spend the whole snorkel trip clearing water instead of looking at fish.

To pick the right one: press the mask against your face (no strap) and inhale gently through your nose. If it stays on without falling, the seal is good. Do that for a few different models. Silicone skirts are softer and last longer than rubber. Low-volume masks (less air space) are easier to equalize and slightly less prone to fogging because there’s less moisture inside.

For fog prevention: new masks need the factory coating scrubbed off. Toothpaste (non-gel, non-whitening) works — rub it on the inside, rinse, repeat. After that, spit or a commercial defogger before each session. Never wipe the inside, just rinse.

You can’t fix a leaky mask with more defogger.