Short answer: Fibonacci wins often but doesn't beat roulette. In 100,000 simulated sessions it finished ahead almost two times in three, yet lost the whole €100 bankroll in nearly a third of them. On average it lost 2.7% of everything wagered, exactly the house edge.
How the Fibonacci system works
Your bets follow the Fibonacci sequence, where each number is the sum of the two before it: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144…
- Bet one unit on an even-money bet such as red.
- After a loss, move one step forward in the sequence.
- After a win, move two steps back (or to the start).
It grows more slowly than Martingale, which doubles after every loss, but faster than D'Alembert, which adds one unit.
How fast the bets grow
With a €1 base bet, here's what a losing streak costs:
| Losses in a row | Next bet | Total lost so far |
|---|---|---|
| 4 | €5 | €7 |
| 6 | €13 | €20 |
| 8 | €34 | €54 |
| 10 | €89 | €143 |
| 12 | €233 | €376 |
Long losing streaks are more common than most players expect. In 200 spins on red, you'll see 6 losses in a row 85% of the time, 8 in a row 37% of the time, and 10 in a row 11% of the time. With a €100 bankroll, a streak of 9 or 10 is usually the end of the session.
A win also doesn't wipe out a losing run. Moving two steps back only recovers part of what you lost, so after a long streak you need several wins to get back to where you started.
We simulated 100,000 sessions
Using the same engine as our free roulette simulator: bets on red, €500 table maximum, a fair wheel, 100,000 sessions per row. "Lost whole bankroll" means the session ended because the money ran out.
| Setup | Sessions in profit | Lost whole bankroll | Average result |
|---|---|---|---|
| Fibonacci, €1 base, €100 bankroll, 200 spins | 62.9% | 31.8% | −€11.54 |
| Fibonacci, €1 base, €100 bankroll, 1,000 spins | 23.7% | 76.1% | −€37.32 |
| Fibonacci, €5 base, €100 bankroll, 200 spins | 26.2% | 73.3% | −€26.61 |
| Fibonacci, €1 base, €500 bankroll, 200 spins | 85.0% | 8.6% | −€19.25 |
| Fibonacci, €1 base, €100 bankroll, 200 spins, American wheel | 54.4% | 39.2% | −€23.48 |
What the numbers show
- Winning often isn't the same as winning money. 62.9% of sessions finished ahead, usually by a small amount. The 31.8% that went bust lost the whole €100. Together that's an average loss of €11.54 per session.
- A bigger bankroll makes it look even better, and lose more. With €500, 85% of sessions finished ahead, but the average loss rose to €19.25 because the rare busts are five times bigger.
- Long sessions catch up with you. Over 1,000 spins only 23.7% of sessions finished ahead.
- Bigger base bets are dangerous. With a €5 base on a €100 bankroll, nearly three sessions in four lost everything.
- The house edge is always the same. In every row, the average loss is about 2.7% of the money wagered (5.3% on the American wheel).
Why Fibonacci feels like it works: most nights you walk away a little ahead, so it's easy to believe you've found an edge. The rare night that goes wrong costs more than all those small wins put together. That pattern of frequent small wins and rare big losses is the signature of every loss-chasing system.
If you enjoy playing Fibonacci
- Decide in advance how far up the sequence you'll go, for example to 13 units, and reset there.
- Keep the base bet at 1% of your session bankroll or less.
- Play European or French roulette, never American.
- Set a loss limit and a time limit. See how to set a roulette budget.
Want to see it for yourself? Choose "Fibonacci" in the roulette simulator and run 1,000 sessions, or compare it with every other system in our strategy comparison.