Product Info--Millimeter to Inches Conversion

8mm is 5/16" or slightly larger than 1/4" (Kismet tiles)

10mm is 3/8" (Krystal tiles)

12mm is 15/32" or slightly smaller than 1/2" (Kismet tiles)

15mm is approximately 5/8” or just over 1/2" (Foilicious tile)

20mm is 3/4" (Krystal tiles and vitreous glass tiles)