Hot-number tracking method
The Andrucci Betting System: How Hot Number Tracking Works
The Andrucci betting system records roughly 30 to 37 recent roulette results, identifies the numbers that appeared most often and then backs those numbers with flat straight-up bets. It is a number-selection method, not a staking progression.
On a fair European wheel, a number that appeared five times in the sample is still only 1 in 37 on the next spin. This guide shows the complete tracking process, lets you test your own result history and calculates the real cost of selecting one, two or three numbers.
Worked version: European single-zero roulette | 37-spin observation | one selected leader | flat stake | stop after the first hit or 35 betting spins.
From 37 Results to One Selected Number
The complete worked sample below contains 37 valid European roulette results. Number 17 appears five times and is the only frequency leader, so it becomes the selected number for the betting example.
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The Exact Andrucci Version Calculated Here
Descriptions of the system vary. Some use 30 observation spins, several target numbers or a different betting window. The calculations on this page use one declared version throughout so the tracker, examples and tables remain consistent.
Use spectator mode, existing history or free roulette. A paid even-money bet adds turnover but no predictive value.
Write down every result from 0 to 36 in order and count the frequency of each pocket.
Select the sole highest-frequency number. A tie means the sample has no unique leader under this version.
Place one fixed straight-up bet for up to 35 spins, stopping after the first hit.
The observation sample does not create an edge. It only supplies a rule for choosing a number. On a fair wheel, the selected pocket remains 1 in 37 on the next European spin, regardless of how often it appeared in the sample.
Paste Your Results into the Andrucci Tracker
Enter European roulette results from 0 to 36, separated by commas, spaces or new lines. The static worked sample is already loaded. The tracker updates every pocket, reports ties and ignores invalid entries such as 00 or 37.
Check the betting phase
Default: one £1 target, a 35-spin cap and the first hit on spin 20.
A first hit on spin 20 returns £36.00 gross after £20.00 of total stakes, leaving £16.00 net.
One Hit Is Not Always a Profitable Cycle
A winning straight-up chip returns 36 units gross, including the original unit. The complete result also includes every stake placed before the first hit and every other selected number that lost on the winning spin.
Complete result when the first selected number hits on spin s
36u - (targets x u x s)
Worked example: two numbers are backed at one unit each. If the first hit arrives on spin 25, the winning chip returns 36 units gross, but 50 units have been staked across the sequence. The complete result is -14 units.
Swipe sideways to compare all columns.
| Targets | Spin cost | Hit by spin 35 | Latest profit | Hit on 35 | No hit | Expected cycle |
|---|---|---|---|---|---|---|
| 1 | 1u | 61.67% | Spin 35 | +1u | -35u | -0.62u |
| 2 | 2u | 85.70% | Spin 17 | -34u | -70u | -0.86u |
| 3 | 3u | 94.82% | Spin 11 | -69u | -105u | -0.95u |
Assumptions: one-unit flat stakes, European single-zero roulette, stop on the first selected hit or after 35 betting spins. For two targets, spin 18 breaks even. For three targets, spin 12 breaks even.
Why Repeats Appear in a 37-Spin Sample
Thirty-seven spins do not form a cycle in which every European pocket should appear once. Independent spins naturally leave many numbers unseen while a smaller group repeats.
The expected number of distinct pockets after 37 fair spins is about 23.57. The worked sample contains 24, almost exactly in line with that expectation. Repetition is therefore evidence of normal short-term variation, not proof that the repeated number is more likely on the next spin. See the wider explanation of roulette odds and probabilities.
What the Recent Results Do and Do Not Tell You
Hot-hand belief
Expecting a recent repeater to continue is a continuation belief. Andrucci follows this idea when it backs the most frequent recent number.
On a fair wheel, the previous cluster does not raise that pocket above its normal next-spin chance.
Gambler’s fallacy
Expecting a number to arrive because it has been absent is a reversal belief. That is the opposite selection rule.
Neither recent repetition nor recent absence makes an independent roulette pocket due.
Wheel bias is a different question. A genuine bias investigation looks for persistent deviation across a much larger dataset or measures physical conditions. A single 37-spin frequency table cannot identify a stable defect or explain why a pocket repeated.
European and American Results Are Not Equal
The straight-up payout remains 35:1 on both standard wheel types. The additional 00 pocket on American roulette reduces the hit probability and increases the expected loss.
Swipe sideways to compare all columns.
Andrucci and Martingale Solve Different Problems
Andrucci is a rule for choosing straight-up numbers. Martingale is a rule for changing the stake after a loss. They create different patterns of exposure and neither changes the underlying house edge.
Andrucci method
- Selects numbers from a recent frequency sample.
- Uses flat straight-up stakes in the version calculated here.
- One selected number has a 1 in 37 European hit chance.
- Main pressure comes from long miss runs and the cost of covering extra targets.
Martingale system
- Usually applies to an even-money bet such as red or black.
- Doubles the next stake after each loss.
- The stake, rather than the selected outcome, changes through the sequence.
- Main pressure comes from exponential stake growth and table limits.
For a simple fixed-stake comparison without recent-number selection, see the Masse Égale method.
Methodology and Assumptions
The figures on this page are calculated from standard roulette payouts rather than simulated profit claims.
- European examples use 37 pockets and a 35:1 straight-up payout, returning 36 units gross.
- The main version observes 37 spins, selects one unique leader and uses a fixed unit.
- The betting phase stops on the first selected hit or after 35 spins.
- The one-, two- and three-target comparisons assume independent fair spins.
- Observation bets are excluded. Paying to generate the sample would add further turnover and expected loss.
- The expected frequency figures use the binomial distribution for 37 independent European spins.
Andrucci Roulette FAQs
What is the Andrucci roulette strategy?
It is a recent-frequency number-selection method. Players record roughly 30 to 37 results, identify the most frequently appearing numbers and then place flat straight-up bets on the selected targets.
How many spins should I track?
Descriptions vary, but 30 to 37 observation spins are common. This page uses 37 so the worked example covers one sample for every pocket on a European wheel. It is still not a complete statistical cycle.
How many hot numbers should I select?
The main example selects one unique leader. Selecting two or three numbers increases the chance of any hit, but it also increases the stake on every spin and makes a late first hit less likely to leave a profit.
Does a hot number become more likely to repeat?
Not on a fair independent wheel. A selected number remains 1 in 37 on the next European spin. Its recent count describes the past sample rather than changing the next result.
Can one winning hit still leave a loss?
Yes. The timing and number of targets matter. With two one-unit targets, a first hit on spin 25 returns 36 units gross after 50 units of total stakes, so the complete sequence remains 14 units down.
Is European roulette better for this method?
Yes, when comparing standard straight-up bets. European roulette has 37 pockets and a 2.70% house edge. American roulette has 38 pockets, including 00, and a 5.26% house edge while keeping the same 35:1 payout.
Keep the Tracking Exercise Separate from a Profit Claim
The Andrucci method can make a session more structured, but it does not predict an independent fair wheel. Set the maximum cash exposure before the betting phase, do not pay for an observation sample solely to create results and do not extend the window because a selected number feels due.