The perfect blind structure: how to design it level by level

The difference between a balanced tournament and a lottery lies almost entirely in the blind structure. Yet it is the part that gets improvised most often: someone copies a structure found online, the tournament starts, and halfway through the night the average stack is worth ten big blinds.

The four numbers to start from

A blind structure is designed backwards, starting from four numbers:

1. Starting stack (e.g. 15,000)
2. Expected number of players (e.g. 30)
3. Target duration (e.g. 5 hours)
4. Level length (e.g. 20 minutes)

These give you the two ends of the structure:

• The first big blind: the standard is 1/100–1/200 of the starting stack. With 15,000 chips, starting at 50/100 gives depth; starting at 100/200 shortens the night.
• The last big blind: by the end, the BB should be worth roughly 1/20 of the total chips in play. With 30 players at 15,000 chips (450,000 total), the tournament will end around a BB of 20,000–25,000.

The number of levels comes from the duration: 5 hours at 20-minute levels is 15 levels. The growth between levels must take you from the first BB to the last one smoothly: in practice, a 25–50% increase per level.

The constraint everyone forgets: chip denominations

A mathematically perfect structure is useless if the blinds cannot be composed with the chips you have in the room. If the smallest denomination is 25, the small blind can never be 60. If the smallest denomination is 100, forget the 150/300 level.

Practical rules:

• Every big blind must be a multiple of twice the smallest denomination, so that the small blind (BB/2) is always composable too. Never blinds with decimals, never small blinds that cannot be paid.
• Prefer "clean" values relative to the big denominations: 1,000/2,000 beats 1,100/2,200.
• Color up the small denominations during breaks, once they are no longer needed.

Antes: when and how much

The ante speeds up the game and fattens pre-flop pots. The three most common variants:

• Big Blind Ante: the player in the big blind pays the ante for the whole table. This is the modern standard: one payment, no counting every hand.
• Button Ante: same idea, but the button pays.
• Classic ante: every player pays. Slower, now rare in live tournaments.

The typical amount is 100% of the big blind for the BB Ante (or 25–50% per player), also rounded to the available denominations. It is usually introduced from the third or fourth level.

Mistakes to avoid

• The killer jump: going from 500/1,000 to 1,500/3,000 triples the cost of a round in a single level. Increases should stay under 50%.
• Useless early levels: 25/50 followed by 30/60 changes nothing. Better fewer, well-spaced levels.
• Ignoring re-buys: if the tournament allows re-buys and add-ons, the chips in play increase. The final BB must be recalculated accordingly, or the tournament will run long.

Don't do the math by hand

All this arithmetic — geometric growth, rounding to denominations, antes — is exactly the kind of work worth delegating. In our free calculator you enter stack, players, duration and chip denominations: the structure comes out already composable, with no decimals. And when you organize for real, in Poker Manager the structure becomes the tournament timer, with automatic level advancement and a TV monitor in the room.