Coaster size: standard coaster dimensions and thickness

The standard coaster size is 4 inches, either a 4 inch circle or a 4 x 4 inch square. A 4 inch coaster fits under most pint glasses, wine glasses, cans and coffee mugs with room to spare. 3.5 inch rounds and squares are the other common size, and they cost slightly less to print. This guide covers coaster sizes, shapes and thickness, and how to set up artwork for printed paper coasters.

Standard coaster sizes

• 4 in round: the most common bar and restaurant coaster.
• 4 x 4 in square: the same coverage as a 4 inch round, with more room for text and corner designs.
• 3.5 in round: a slightly smaller coaster for bars, events and wedding favors.
• 3.5 x 3.5 in square: a compact square that suits small tables and favor sets.
• Custom die-cut shapes: hexagons, ovals, scalloped edges, logos and other shapes cut with a custom die.

Larger coasters of 4.25 inches or more are sometimes used under mugs, stemless wine glasses and large cocktail glasses, but they take more space on a crowded bar.

Glass and mug sizes

A coaster needs to be wider than the base of whatever sits on it, with enough margin to catch condensation that runs down the glass.

• Pint glasses and beer cans have a base of roughly 2.5 inches.
• Rocks glasses and most coffee mugs have a base of about 3 to 3.25 inches.
• Wine glasses usually have a foot of about 3 inches.

A 4 inch coaster covers all of these. A 3.5 inch coaster works for most glasses but leaves less margin under mugs.

Coaster thickness

Paper coasters are printed on pulpboard, a thick, absorbent board made from wood or recycled fiber. Thickness is measured in points, where one point is one thousandth of an inch.

• 40pt (about 1 mm): a lighter coaster for events, giveaways and high-volume bar use.
• 60pt (about 1.5 mm): a heavier coaster that absorbs more moisture and feels more substantial.

We print coasters on recycled pulpboard and chipboard. See our 60 pt coaster board for the heavier stock.

Paper coasters vs cork and plastic

Uncoated pulpboard soaks up condensation, prints in full color and can be composted after use. Cork, rubber and laminated coasters last longer, but they are harder to recycle and cost more per piece. For bars, restaurants and events that go through coasters quickly, paper is the practical choice.

Setting up coaster artwork

• Build the file at the finished size, such as 4 x 4 in, and add 0.125 in of bleed on every side. A 4 in coaster file is 4.25 x 4.25 in with bleed.
• For round coasters, design on a square artboard and place the circle cut line exactly in the center.
• Keep logos and text at least 0.25 in inside the cut line, so nothing is trimmed off.
• Use bold shapes and large type. Pulpboard is absorbent, so very fine lines and small text can soften.
• Coasters can be printed on one side or both. Many bars use the back for a drink special, an event date or a QR code.

At 300 ppi, a 4 inch coaster with bleed is 1275 x 1275 pixels. Our guides to bleed in printing and print-ready files cover file setup in more detail.

Ordering custom coasters

For logo coasters for a restaurant, bar or event, see our custom paper coasters. For wedding favors, see our personalized photo coaster gift sets. Restaurants can pair coasters with printed menus and table tents.

Common questions

What is the standard size for a coaster?

4 inches is the standard coaster size, as a 4 inch round or a 4 x 4 inch square.

How thick are paper coasters?

Most paper coasters are 40pt to 60pt pulpboard, which is about 1 to 1.5 mm thick.

Will a 3.5 inch coaster fit a coffee mug?

It fits most mugs, since a typical mug base is about 3 to 3.25 inches across, but a 4 inch coaster leaves more margin.

Are paper coasters compostable?

Uncoated pulpboard coasters can be composted after use, because they have no plastic laminate or cork backing.