Tools / Bubble Factor Calculator
Bubble Factor Calculator & Formula
Enter the stacks left and the payouts still in the pool. The matrix below shows the real equity every player needs against every other player to call an all-in - not a rule of thumb, the actual ICM math for this exact table.
Players remaining
6 players · 65,500 chipsPayouts (place 1, 2, 3...)
Pool: $5,900Places 4-6 pay nothing.
Bubble factors updated for 6 players.
Required equity to call an all-in
Rows are hero, columns are villain - click a name above to set who's deciding, or just read any cell as “row calls column’s shove.”
| Hero \ Villain | Player 1 | Player 2 | Player 3 | Player 4 | Player 5 | Player 6 |
|---|---|---|---|---|---|---|
| Player 1 | - | 60.0% | 57.7% | 55.7% | 54.0% | 52.1% |
| Player 2 | 62.7% | - | 58.6% | 56.4% | 54.3% | 52.3% |
| Player 3 | 61.1% | 59.9% | - | 56.7% | 54.5% | 52.4% |
| Player 4 | 59.3% | 58.2% | 57.5% | - | 54.6% | 52.5% |
| Player 5 | 57.2% | 56.3% | 55.7% | 55.3% | - | 52.5% |
| Player 6 | 54.4% | 53.9% | 53.5% | 53.2% | 52.9% | - |
Each all-in is modeled for the smaller of the two stacks (the chips actually changing hands). Cells in orange need real equity, not a coin flip, to call profitably. A “-” means the all-in can't change that player's payout (a busted stack, or prizes that don't depend on it).
The bubble factor formula
Bubble factor compares what an all-in does to your tournament equity, not your chips:
Both sides are measured in ICM dollars (or percent of the prize pool) against your equity right now. Say you have $20.00 of equity on a bubble. Doubling up would take you to $28.00, a gain of $8.00, and busting takes you to $0, a loss of $20.00. Your bubble factor in that confrontation is 20 ÷ 8 = 2.5, so a straight coin flip is a losing call: you need 2.5 ÷ 3.5 = 71% equity to break even.
That breakeven is the formula B ÷ (1 + B), which holds when the chips you risk equal the chips you can win. When pot odds are involved, start from the chip-EV breakeven p instead: the equity you need becomes B·p ÷ (B·p + 1 − p). The difference between that and p is the risk premium, the same pressure stated as extra equity rather than a ratio.
Bubble factor to risk premium converter
You need 60.0% equity to call, against 50.0% in chip-EV terms.required = B·p / (B·p + 1 − p) = 1.50 × 0.500 / (1.50 × 0.500 + 0.500)
Why the matrix isn't symmetric
Reading a row is asking “what does this player need to call a shove?” The same two players, read as different rows, almost never need the same number. A short stack calling a covering stack's shove is risking its entire tournament for a double-up that's worth less, per chip, than the chips it's risking - that needs real equity. The covering stack calling the short stack back is risking a much smaller fraction of its own equity for the same double-up - that's much closer to a coin flip.
This is exactly the effect a chip-EV push/fold chart can't see: two hands can look identical in isolation and require completely different equity once the payout structure and both stacks are priced in.
This calculator answers “what equity do I need” for a spot you already have. Building the instinct for which hands actually clear that bar, position by position, is what ICM practice in the app trains.
Practice ICM spots free →Common questions
- What is bubble factor in poker?
- Bubble factor is the ratio between the tournament equity you'd lose by busting a confrontation and the equity you'd gain by winning it. A bubble factor of 1 means the spot is chip-EV neutral - a coin flip breaks even. Above 1, the spot is worth less than its chip count implies, so you need more than 50% equity to profitably get the chips in. The term comes from Lee Nelson, Steven Heston, and Tysen Streib's Kill Everyone.
- Why is my bubble factor different from my opponent's, for the same hand?
- Bubble factor isn't a property of the pot - it's a property of each player's own stack and tournament life relative to the payout structure. A short stack risking its whole tournament against a covering stack has a much higher bubble factor than the covering stack risking the same chips against the short stack, because the short stack has far more to lose relative to what it gains.
- How is the required equity calculated?
- From bubble factor B, the breakeven calling equity is B / (1 + B). This calculator gets B by running full ICM twice for each pair of players - once assuming hero wins the confrontation, once assuming hero loses it - and comparing both to hero's current ICM equity.
- How do you convert bubble factor to risk premium?
- Take the chip-EV breakeven p from the pot odds. The equity you need with bubble factor B is B·p / (B·p + 1 − p), and the risk premium is that number minus p. At an even double-up (p = 50%) a bubble factor of 1.5 needs 60% equity, a 10-point risk premium. Going the other way, B = q(1 − p) / (p(1 − q)), where q is breakeven plus the premium.
Key terms
- Bubble Factorglossary
- The Bubbleglossary
- Risk Premiumglossary