The Fibonacci betting system helps casino players determine how much to stake when playing blackjack, roulette, baccarat and other popular games. It is a negative progression system, meaning you increase your stake each time you lose a wager. Fibonacci system betting is considered to be safer than following alternative strategies like the Martingale, but it still offers the potential for exciting profits. This Fibonacci strategy guide will explain how the system works, round up the pros and cons of using it, and describe how to apply the Fibonacci system to a variety of games at online casinos.
How Fibonacci System Works
Leonardo Bonacci of Pisa was renowned as the most talented mathematician of the Middle Ages. He went by the name of Fibonacci and found fame by popularising the numeral system across Europe in the early 13th century. Nowadays he is best known for his famous Fibonacci sequence, which remains popular some 770 years after his death.
He created the Fibonacci sequence to calculate the growth of rabbit populations. The Fibonacci numbers, commonly denoted Fn, form a sequence whereby each number is the sum of the proceeding two numbers, starting with 0 and 1. If you are into algebra, Fn = Fn−1 + Fn−2 for n ≥ 2 with F0 = 0, F1 = 1, which gives the sequence F0, F1, F2.
However, you do not actually need to concern yourself with any of that if you want to follow the Fibonacci strategy. You just need to remember the sequence it produces, or have the ability to work it out in your head. Every new number equals the sum of the previous two numbers, so for a Fibonacci betting system, you would go with: 1-1-2-3-5-8-13-21-34-55-89-144-233-377-610-987, and so on.
You can then use this sequence to determine how much you should wager on each spin of the roulette wheel, hand of blackjack or baccarat, or throw of the dice in craps. It is generally used on even money bets, where the chance of success is roughly 50/50, such as red/black or odd/even on roulette.
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Start off by setting aside a bankroll, which is an amount of money that you are comfortable with losing in a worst-case scenario. Assign a certain proportion of this bankroll as your base unit. It is unwise to go higher than 5% of your bankroll as a base unit amount, and many find 2% to be a safer choice. The base unit amount must not change while you are playing.
Let’s say you have €500 to play with, and opt for 2% of your bankroll as a base unit. That amounts to €10. You would start off by betting €10, which is 1 unit (the sequence begins with 1). If you were to win, you would start again by placing another €10 bet. However, if you lose, you move up the sequence: 1-1-2-3-5 and so on.
If you lose an initial €10 bet, your second bet would also be for €10 in this example. If that lost, you would place a €20 bet for your third wager, a €30 stake for your fourth bet, a €50 stake for your fifth bet, and so on, until you eventually win. You multiply your base unit by the number in the sequence to determine the amount you should wager.
If you lose a bet, move one number up the sequence. If you win, move two numbers down the sequence. Continue following that pattern as you play in order to use Fibonacci system betting. You simply work your way through the chain until you win, and then work your way back two places in the sequence and keep going.
ℹ️ This chart explains a hypothetical application of the Fibonacci betting system in practice:
Wager | Stake | Result of Bet | Balance |
---|---|---|---|
1️⃣ First Bet | €10 | Loss | -€10 |
2️⃣ Second Bet | €10 | Loss | -€20 |
3️⃣ Third Bet | €20 | Loss | -€40 |
4️⃣ Fourth Bet | €30 | Loss | -€70 |
5️⃣ Fifth Bet | €50 | Win | €30 |
6️⃣ Sixth Bet | €20 | Loss | €10 |
7️⃣ Seventh Bet | €30 | Loss | -€20 |
8️⃣ Eighth Bet | €50 | Win | €80 |
9️⃣ Ninth Bet | €20 | Loss | €60 |
🔟Tenth Bet | €30 | Win | €120 |
In this example, you have won just three out your 10 bets, but you would emerge with a profit by increasing your stake after each loss. If you had followed the more aggressive Martingale system while betting, that initial streak of four losses would have been a lot more damaging. The Fibonacci strategy is therefore considered to be safer than other progression systems.
The Fibonacci betting system is a negative progression system, as you decrease your stake after a win and increase it after a loss. Some players prefer to follow a reverse Fibonacci strategy. This involves the same sequence, but you move up the sequence after winning and down after losing. That is a more aggressive and potentially riskier strategy, but it can yield high returns if you enjoy a winning streak.
Fibonacci Betting System Pros and Cons
There are several advantages to using the Fibonacci betting system:
Pros | Cons |
---|---|
👍It allows you to win your losses back. If you keep moving up the sequence each time you lose, you will eventually recoup your losses by continuing to double your stake each time. The proviso is that you have a large enough bankroll to keep going until you secure a win. A long losing streak could wipe you out if you cannot continue doubling after each loss, which is why it makes sense to set a small portion of your bankroll as your base unit | 👎It is more complicated than alternative strategies. For example, the D’Alembert negative progression strategy simply requires you to increase your stake by one base unit each time you lose, or decrease it by a unit each time you win. That is a lot easier to follow than 1-1-2-3-5-8-13-21-34-55-89 and so on. If you miscalculate and stake the wrong amount by accident, the Fibonacci strategy would be jeopardised, so you must stay on top of it throughout your casino session. |
👍It is not a particularly aggressive strategy, so you are unlikely to quickly blow your bankroll while playing your favourite casino games. It appeals to players that are reasonably cautious. | 👎Fibonacci system betting can grow pretty daunting when you embark on a losing streak. For example, if your initial wager is €10 and you lose nine straight bets, you would have to stake €550 on your 10th bet. You will therefore need a sizeable bankroll in order to cover the eventuality of a bad streak. Such bad streaks are unusual in games of chance where the outcome is around 50/50, but they do happen and you must be prepared for them. |
👍Often yields consistent small profits, as you simply start again each time you win at the start of your session, or move back two places with each win. | 👎You are unlikely to land huge profits by using the Fibonacci strategy, as it encourages you to reduce your stake each time you win. It is more focused on securing consistent small profits and imposing damage limitation on potential losses rather than chasing a huge payout. |
👍Gives you an element of control over your bankroll. It is a pretty rigorous system, and it helps you think about the amount you stake on each bet, rather than simply increasing or decreasing your wagers at random. | 👎No system removes the house edge on casino games. Like other progressive strategies, the Fibonacci betting system is used on bets of a roughly 50/50 chance, but there is always a built in house edge, which helps the casino out in the long-term. However, you can claim casino bonuses and promotions, which reduce that house edge, and many people enjoy long sessions in the casino by following the Fibonacci strategy. |
👍The Fibonacci betting system is reasonably easy to follow, particularly if you have the sequence in front of you. |
Fibonacci Blackjack Betting System

Blackjack is beloved by gamblers across the world due to the speed, simplicity and excitement it offers. The house edge is very small on this game: classic blackjack has a theoretical RTP (return to player) of 99.41%, meaning your chances of winning each hand are very close to 50%. It is therefore the perfect game for the Fibonacci betting system.
If you want to apply a Fibonacci strategy to blackjack, make sure you a clear bankroll for your session. Choose a proportion of that bankroll for your initial wager, and remember that this will be your base unit. The Fibonacci betting system only works if you have a large enough bankroll to cover a lengthy losing streak. If the minimum bet at a table is €5 and you only have €30 to play with, you might want to consider an alternative strategy to Fibonacci system betting.
Let’s say you have €250, and you decide that €5 will be your unit price. If you are playing online blackjack, you can have the Fibonacci sequence on your computer or printed in front of you: 1-1-2-3-5-8-13-21-34. This translates to €5, €5, €10, €15, €25, €40, €65, €105, €170 and so on if your unit is €5 when following the Fibonacci strategy.
Place your first bet at €5. If it wins, start the sequence from the beginning. If you lose, move forward by one place, wagering €5. If you lose again, wager €10 the next time, then €15, then €25, then €40, and so on, until you win. If you were to win at €40, you would move back two places for the next wager, meaning you would bet €15 on your next hand. Continue moving up one place with each loss and down two places with each win until your session comes to an end.
There are no specific rules to follow in the event that you land a blackjack, successfully double down or successfully split your hand. Many players using the Fibonacci strategy simply add the extra winnings to their bankrolls and continue following the sequence. The best way to secure a large profit when playing a Fibonacci strategy is to land five consecutive wins, particularly if you are already reasonably deep into the sequence when you pull it off.