Stack.bet grades each placement by how far it lands from the middle of the tile below. A placement is a Perfect, a cut or a Miss. The grade comes from the authoritative placement offset calculated by the game service, and it can only change the bust chance of the tile you are placing. No grade guarantees that a placement will survive. The grades are what make Stack.bet a form of skill gambling: how precisely you place changes the risk you carry.
Who determines the placement grade
The player sends an intent to place the next tile using a pointer or keyboard. The command identifies the round and the next tile; it does not get to declare the grade, the survival result or the bust outcome. The game service evaluates that intent against the authoritative tile motion, calculates the placement offset, and passes that offset into the game engine.
The engine then grades the offset with the rules below. This keeps the grade and settlement inputs on the authoritative game path instead of accepting a browser-supplied result.
Every tile is 100 pieces of itself
Each tile is measured as 100 pieces of its own width, so one piece is 1 percent of the tile you are landing on. How many whole pieces you miss by decides the grade:
Placement | How far from the middle | Added to this tile's bust chance |
|---|---|---|
Perfect | Within 5 percent of the tile | Nothing |
Cut | More than 5 percent, with any overlap left | 0.1 percent for every whole piece missed |
Miss | No overlap at all | The round ends |
Only whole pieces count, so part of a piece rounds down: a placement 16.7 percent off the middle misses 16 whole pieces and adds 1.6 percent. Just missing a Perfect adds 0.5 percent, and the most a cut can add is 9.9 percent, for a placement 99 pieces off. Each standing tile shows its own result on screen: a green +0% for a Perfect and an orange figure, such as +1.6%, for a cut.
The rules are the same on every tile. The tile always moves at the same speed, and a miss costs the same share of whatever tile you are on, so tile 1 and tile 25 are graded in exactly the same way. Only the published base bust chance rises as the tower climbs.
What a placement does to the tower
A Perfect does more than avoid extra risk. The new tile grows by 5 percent of its width, centred on the tower, so the next target is a little larger. On a phone a tile can grow to at most 1.3 full tiles, and on a desktop to at most 2.5.
A cut trims the part that hangs over the edge. The trimmed piece falls away, and the next tile is as wide as what is left. As the tile gets smaller the tower shakes more; on a full-width tile it does not shake at all. The tower and the moving tile shake together, so what you see is exactly what is graded. There is no sway.
How the bust chance of a tile is set
For a placement that lands, the engine starts with the published base bust chance for that tile and adds the cost of the pieces missed. Nothing is carried into the next tile: whatever happened on this one, the next tile starts again at its own published base chance.
Tile bust chance = base bust chance + 0.1% × whole pieces missed
Maximum = 95%, a cap the published table never reaches: tile 30 with a 99-piece cut comes to 80.402%
A cut adding 1.6 percent does not mean the game has gained a 1.6 percent house edge. The base probability, the placement and the generated bust value are separate parts of the round calculation.
A tile 1 example
Tile 1 currently has a base bust chance of about 4.7619 percent. The table shows the chance the bust roll has to beat for some example placements.
Placement | Pieces missed | Added | Tile 1 bust chance |
|---|---|---|---|
Perfect | 0 to 5 | 0% | 4.7619% |
5.5% off | 5 | 0.5% | 5.2619% |
16.7% off | 16 | 1.6% | 6.3619% |
40% off | 40 | 4.0% | 8.7619% |
99% off | 99 | 9.9% | 14.6619% |
These are calculation examples, not observed win rates or forecasts for a player. Read the separate explanation of base house edge and tile risk for how a tile's growth factor and base bust chance fit together.
What precision is worth over a round
Because the base maths carries zero house edge, a player who lands every tile Perfect gets back 100 percent over the long run wherever they cash out. Each missed piece lowers that, and the cost compounds the higher you climb. Modelled on the live configuration, with the same accuracy on every tap and cashing out at the same tile every round:
Cash out at | Multiplier | Every tap Perfect | 10% off | 20% off | 40% off |
|---|---|---|---|---|---|
Tile 3 | 1.16x | 100% | 96.9% | 93.8% | 87.9% |
Tile 5 | 1.28x | 100% | 94.9% | 89.9% | 80.7% |
Tile 10 | 2.30x | 100% | 89.6% | 80.3% | 64.1% |
Tile 20 | 112.38x | 100% | 77.2% | 59.3% | 34.7% |
A tap 10 percent off the middle misses 10 pieces and adds 1 percent to each tile's bust chance. That costs about 1 percent of the return per tile, not 10 percent in total.
What a Miss means
A placement with no overlap at all is a Miss. The engine needs both a landed placement and a surviving bust roll, so a Miss ends the round even if the generated bust value would otherwise have cleared the threshold.
A landed placement is not an automatic win either. Perfect and cut placements still face the tile's bust chance. This is why Stack.bet should not be described as a pure-skill or chance-free game.
What placement grades do not prove
A Perfect grade does not guarantee survival or a profitable round.
A grade does not remove the base bust risk or the generated chance component.
The 5 percent and 1 percent pieces are measured against the tile itself, not against your screen in pixels.
The cost of a cut is not an additional published house-edge percentage.
One result does not predict the next round or establish a player's long-term outcome.
Stack.bet involves real-money gambling and the full stake can be lost. Review the game and risk disclosures and use the available responsible-gaming controls before playing.
Methodology and change control
This article was reviewed on against the live public game configuration, the authoritative placement-intent contract and the game engine's grading and survival calculations. The examples use the current unrounded tile 1 base bust chance, and the return table models the live risk table.
The figures describe the standard public configuration, not independently measured player results. If the grading rules, the risk table or the placement authority change, the examples and the review date must be updated.