What coaster sizes do you offer? October 26, 2020 19:12 Updated Follow The standard coaster sizes we offer are 3.5" x 3.5" and 4" x 4"; and the maximum custom size we can print is 12" x 12". Related articles Can I order a custom shape? What kind of inks are used for eco stickers? How do I create my coaster design? Can I vacuum over the stickers? How do I prepare files with white ink?