What is the best sealant for painted kitchen cabinets?

use epoxy sealer it really do a great job.

Use a non yellowing polycrylic finish

If you are painting stained cabinet be sure to use an oil based primer before painting. Cabinet companies use catalyst in their paint to create a harder finish. I believe you can buy these in you local paint store. After you add it to your paint, it will not keep though. There is no reason to need to add a sealer after you paint. It's already durable and washable. I would stay away from valspar paint, it has a rubbery finish. My favorite cabinet paint is Sherwin Williams Proclassic.

Polyurethane is a great sealant! you just want to make sure it is compatible with the paint you use.

Polyurethane is just about the only easiest, best sealer. I use at least three coats on painted surfaces. Water based poly dries quick and remains clear. Comes in satin, semi gloss, and gloss. I prefer Minwax products but any brand will work. Also I like to use a foam brush to get a smooth finish.

Thanks.

Auto wax! I use it on my appliances too!

Robyn, Polycrylic is polyurethane. It's what I like to use. I'm a fan of Minwax products