Mexican Train Dominoes Double-12

The Standard 91-Tile Set

When I built the Mexican Train game for this site, the set size was the one decision that made itself. Double-12 is the set boxed Mexican Train products ship with, the set the most common rules assume, and the set almost everyone means by Mexican Train. So that is what you get here: the full 91-tile double-12 game, free in your browser.

This page covers everything specific to the double-12 set — tile count, why it became the standard, hand sizes, the 13-round structure, and boneyard depth at different table sizes. For the complete play-by-play, the Mexican Train rules page walks through every rule in order.

What Is a Double-12 Domino Set?

A double-12 set contains 91 tiles: one of every unordered pair of pip values from 0-0 through 12-12. That includes all thirteen doubles — 0-0, 1-1, 2-2, and so on up to 12-12. The count follows a simple formula: a double-n set has (n+1)(n+2)/2 tiles, so double-12 gives 13 × 14 / 2 = 91.

For comparison, the familiar double-6 set in most kitchen drawers has just 28 tiles, and a double-9 set has 55. The jump to 91 is what lets Mexican Train scale from a head-to-head duel to a full tabletop party of eight, with generous hands and a boneyard still worth drawing from.

Why Is Double-12 the Standard for Mexican Train?

Because it is the set the game was packaged and sold with. Boxed Mexican Train sets ship with 91 double-12 dominoes, a station hub, and train markers, and the most common published rules are written around that box. A rules chart or score sheet that says Mexican Train without qualification means double-12.

The set size also fits the game's structure perfectly. Each round is started by a different double placed in the station as the engine — and a double-12 set has exactly thirteen doubles, giving the classic 13-round game its shape. Smaller sets work the same way with fewer rounds, but double-12 is the version the game grew up with, and it is the only set our online game uses.

How Many Dominoes Do You Draw?

A common dealing chart for tabletop play with a double-12 set looks like this — though published rule sets genuinely vary by a tile or two, so treat it as a solid default rather than gospel:

Some boxed instructions deal 16 tiles to two players and step down from there; others land a tile higher or lower at several counts. None of it changes the game — what matters is that everyone draws the same number and enough tiles remain in the boneyard.

In the game on this page, every player is dealt 15 tiles, matching the most common chart for tables of 2 to 4.

How Many Rounds Is a Full Game?

A full double-12 game is 13 rounds. Round one uses the double-12 as the engine in the center station; each following round steps down one double — 11-11, then 10-10 — until round 13 is played around the double-blank. Lowest total score across all rounds wins.

Thirteen rounds is a long evening, and shortening the game is standard practice — published rules explicitly leave the round count up to the group. Our online game builds that choice in with four match lengths, selected in the setup screen:

• Quick — 1 round, a single hand from deal to score.
• Blitz — 3 rounds.
• Short — 7 rounds (the default).
• Full — the classic 13 rounds, engines counting down from 12-12 to 0-0.

Scoring is identical at every length: pips left in hand each round, round winner scores zero. The full breakdown lives on the scoring guide.

How Big Is the Boneyard?

The boneyard is whatever remains after the engine is set aside and the hands are dealt. In our game the engine is pulled from the set and placed in the station before the deal, so 90 tiles get split between hands and boneyard. With 15-tile hands that works out to:

A deep boneyard changes how a round feels. With two players and 60 tiles in reserve, getting stuck usually just costs a draw and a turn. With four players and only 30 tiles left, the boneyard can run dry late in a round — and once it is empty, a stuck player simply passes and marks their train, making open trains far more common in the endgame.

Playing Double-12 Mexican Train on Card & Puzzle

The game embedded above always plays with the standard 91-tile double-12 set — free, in your browser, no download and no account. You can play solo against 1 to 3 AI bots or hand the device around in local pass-and-play, with up to 4 players at the table in any mix.

One honest note: this page does not preconfigure anything. When you press Play, the setup screen is where you choose your player count, bot difficulty (Easy, Medium or Hard) and match length. The double-12 set is the one thing you never have to pick, because it is the only set the game deals.

Every deal is genuinely random and reproducible from its seed — no rigged shuffles, no difficulty rubber-banding. Matches resume exactly where you left them, and the Daily Challenge uses a public date-based seed so every player worldwide faces the same deal.

Ready to Play?

Scroll up and press Play to deal your first double-12 hand. For a table size tuned to your taste, the 2-player version is the tightest, most tactical way to play, 3 players balances speed against a deep boneyard, and the 4-player version is the classic full-table experience.

New to the game entirely? Start with the rules reference for every rule in order, check the scoring guide before your first multi-round match, or head back to the main Mexican Train Dominoes page for the full overview.