N95s and KN95s* work significantly better than cloth or surgical masks at preventing the spread of COVID-19. Each filters 95% of aerosol particulates when properly fitted (compared to 30-60% for cloth masks and 40-80% for surgical masks). Head strap masks generally work better than the ones with ear loops as the head straps create a tighter fit, but some people struggle with them. The best mask is the one you will wear consistently. You can also buy connectors that turn the ear loops into a head strap.
Both N95s and KN95s come in a variety of shapes, which will also affect fit. COVID is airborne so fit is very very important; you don’t want little gaps between the mask and your face. Every person’s face is different. What works best for someone else’s face might not work best for you. If your mask comes with a nose wire, make sure to mold it to fit your face properly.
Mask Bloc LA is a mutual aid project to distribute free masks in the LA area. There’s also a mask bloc for Long Beach.
WellBefore and Bona Fide Masks generally have the cheapest N95s and KN95s I’ve found from reputable distributors.
Armbrust sells a sampler pack to help you figure out what shape fits your face best.
Project N95’s shop has closed but they still have a directory of other authenticated distributors to buy from.
BreatheTeq and EvolveTogether sell envelope style KN95s, which tend to fit better for people with a lower nose bridge. Both come in multiple colors, BreatheTeq comes in 4 sizes.
More options for colors and designs: MaskC, Private Stock Labs, and Vida.
Readimask sticks to your face and has no metal so it’s MRI safe. The lack of straps could also make it helpful for hair appointments and things like that.
KF94s and FFP2s* also offer a very similar level of protection (94% of aerosol particulates filtered when properly fitted) and come in a lot more colors and designs:
BeHealthyUSA (KF94), MaskLab (FFP2), and FamilyMasks (KF94)
FamilyMasks sells sample packs so you can figure out which size fits you best, and they also have some with Disney princesses and Iron Man if you’re trying to convince a kid to keep theirs on.
You can also re-use these masks several times as long as they’re not too soiled, but you want to let them hang out in a cool, dry place for a few days between wears. More details here. Do not wash them as that damages the filters.
If you want the most thorough reviews and testing data on all of the many mask options, there is a Google folder from @masknerd on Twitter.
*The different classifications refer to which national or international body the masks are regulated by. N95 is the US standard, KN95 is the Chinese standard, KF94 is the South Korean Standard, and FFP2 is the European standard.