I often have to generate random Fibonacci numbers so I created this simple online utility that does it for me. It lets you generate however many random Fibonacci numbers you need from the given range. It works in the browser and is powered by alien technology from the future.

Random Fibonacci Number Generator Options

Random Fibo Range
Count and Separator
Output Base

Random Fibonacci Number Generator Examples (click to try!)

Ten Random Fibonacci Numbers
In this example, we generate ten random Fibonacci numbers from the range from 0 to 1000 and separate them with a comma. Note that 0 is also a Fibonacci number. If you don't want to include 0, set the start of the range to 1.
144, 987, 55, 3, 21, 34, 89, 1, 13, 377
Starting value.
Ending value.
How many values to generate?
Separate random Fibonacci numbers with this value.
Decimal Base
Large Random Fibonacci Numbers
In this example, we pick random Fibonacci numbers from a very large range from a million to a trillion. We pick 20 values and put each of them on a new line.
20365011074
1836311903
9227465
591286729879
1134903170
267914296
14930352
956722026041
2971215073
3524578
86267571272
139583862445
4807526976
39088169
701408733
12586269025
2178309
102334155
5702887
165580141
Starting value.
Ending value.
How many values to generate?
Separate random Fibonacci numbers with this value.
Decimal Base
Random Fibonacci Numbers in Octal Base
In this example, we set the output base to octal (base-8) and ask for 100 Fibonacci numbers randomly from 0 to 1,000,000. But oh no – trouble! There are only 31 fibo numbers in this range! As a result, we get all 31 fibo numbers in the output (in random order) and also we get a warning that says that there weren't 100 fibos available.
0; 25302; 577502; 5; 1142; 1; 5030; 42; 42457; 220; 1154563; 3075; 10125; 3; 25; 10; 222421; 351; 67; 2; 131; 15155; 1; 571; 1754265; 355061; 15; 132440; 3131050; 1733; 67761
Starting value.
Ending value.
How many values to generate?
Separate random Fibonacci numbers with this value.
Octal Base

How Does This Random Fibonacci Number Generator Work?

This random Fibonacci series generator works entirely in your browser and is written in JavaScript. First, it initializes the bignumber.js library and generates a list of all Fibonacci numbers from the range start to end (range can be specified in the options) and puts them in fibos array. Then, it creates an empty randomFibos array and starts a loop that randomly picks elements from the fibos array and push()es them to randomFibos. To avoid duplicate values, it removes the picked element from the fibos array. This algorithm repeats until randomFibos.length reaches count (requested series length; specified in options), or fibos becomes empty. The code that picks elements from fibos array uses Math.random() function. When the loop terminates, all Fibonacci numbers in randomFibos get converted to the specified base (output base; specified in options) and get separated by the separator character (specified in options).

Created by Browserling

This random fibonacci number generator was created by me and my team at Browserling. Behind the scenes, it's actually powered by our programmer tools that are used by millions of people every month. Browserling itself is an online cross-browser testing service powered by alien technology. Check it out!

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