Dice Size Guide: 12mm, 16mm, 20mm, and Oversized Explained

Dice size sounds trivial until you hold a set that is too small to read or too heavy to roll comfortably. Size is measured in millimetres, usually by the edge length of the d6, and it affects readability, feel, shipping weight, and cost. Here is what the common sizes mean and how to choose.

What is the standard dice size?

The standard tabletop dice size is 16mm, measured on the six-sided die, and it is the default for most role-playing and board-game sets. It balances readability, feel in the hand, and cost, which is why the majority of custom 7-piece polyhedral sets are built around 16mm.

Common dice sizes and what they are best for

• 12mm (mini) — compact travel sets, pouches, and games that need lots of dice; harder to read for some players.
• 16mm (standard) — the everyday default for RPG and board-game sets; the safest choice for a custom line.
• 19–20mm (large) — easier to read and more premium in the hand; common for a statement d20 or a heavier set.
• 25mm and up (oversized) — display pieces, collector d20s, giveaways, and accessibility for players who need larger numbers.

Does the d20 come in a different size?

In a standard polyhedral set the dice are proportioned so they read consistently, with the d20 naturally larger than the d6. Many brands also sell an oversized standalone d20 — often 25mm to 55mm — as a hero piece or collector item, especially in metal and gemstone where the size shows off the material.

How does size affect custom dice cost?

Bigger dice use more material, so size moves the price, and it matters most for metal and gemstone where the raw material is the main cost. A 25mm gemstone d20 uses far more stone than a 16mm one and is priced accordingly. For resin and acrylic the difference is smaller. Tell us the size you want and we will factor it into your quote.