How Many Dominoes Are in a Set?

A standard double-six set has 28 tiles. That is the set almost every game you have played was played with, and the one freshIvories uses.

Why 28?

A domino is an unordered pair of numbers from 0 (blank) to 6. Unordered matters: the 3-5 and the 5-3 are the same tile, so you count each combination once. Seven possible numbers, every pairing including a number with itself, no duplicates.

The formula is (n+1)(n+2)/2, where n is the highest number in the set. For a double-six that is 7 × 8 ÷ 2 = 28.

• 7 doubles — 0-0 through 6-6
• 21 non-doubles — every other pairing
• 168 total pips across the whole set

The bigger sets

Larger sets extend the same pattern. They are common in Mexican Train and in games built for bigger groups:

• Double-six — 28 tiles
• Double-nine — 55 tiles
• Double-twelve — 91 tiles
• Double-fifteen — 136 tiles
• Double-eighteen — 190 tiles

How many you actually hold

The hand size depends on how many people are at the table. Two players typically draw seven each; three or four players draw fewer so the boneyard still has tiles to pull from. Whatever is left after the deal is the boneyard, and in Block mode there is no boneyard at all — you pass instead of drawing.

Knowing the set cold is more useful than it sounds. Once you can picture all 28, you can start working out what your opponent is holding from what they have not played.