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

Random Byte Generator Options

Random Byte Range
Count and Separator
Random Byte Base

Random Byte Generator Examples (click to try!)

Binary Bytes
In this example, we generate 32 random bytes in the binary base. We also change the separator symbol to the newline symbol so that each byte gets put on a separate line.
11110000
11110101
01111000
11011000
01100111
00001001
10101110
01001011
11001000
00001100
00010010
11100011
11100001
01011001
10111101
11010111
11111110
00110101
00101101
01010101
10010110
01111100
11000110
01100100
00110010
10001111
10000001
11101011
10100011
11010101
01101110
01100101
Starting value.
Ending value.
How many bytes to generate?
Separate random bytes with this value. (Space by default.)
Binary Base
Hex Bytes
This example generates 64 random hexadecimal values from the range [0, 1024] and uses the comma symbol to separate them. Values up to 255 fit in a single byte but values from 256 to 1024 need two bytes. In hex, values 0 to 255 have two digits 00 to ff but values 256 to 1024 have three digits 100 to 400.
39b, 383, 215, 3f8, 196, 73, 3ea, 43, 21, 26e, 3fd, 99, 35e, 5f, 28a, 1a0, 19d, 327, 2fe, 397, 2c5, 29b, 24c, 331, 230, 1f0, 2e0, 3ca, 117, 345, 106, 0a, 2e4, 332, 52, 199, 10, 25a, 200, 338, 38d, c4, fe, 346, e6, 1bf, 25e, 195, 247, 34e, 3c1, 2c9, 1ab, 23b, 175, 30e, 1c4, fd, 2e3, ce, d6, 09, c3, 1e
Starting value.
Ending value.
How many bytes to generate?
Separate random bytes with this value. (Space by default.)
Hexadecimal Base
Bytes in Base 50
In this example, we set the custom base to base-50, and generate 50 random bytes, separated by semicolons. Base 50 uses 10 digits (0-9), 26 lowercase letters (a-z) and the first 14 uppercase letters (A-N).
1G; 3d; 2n; 4u; v; o; 3G; 1G; 3t; 3v; 3C; 2a; 1r; 55; 46; b; 3; 4b; 2b; 4d; 1v; 2L; 23; 3E; 2p; 3o; 2y; 4m; v; 10; 4I; 1L; 2F; 18; 2e; 8; 4j; 2f; 4A; 4J; 2N; 2C; 37; 2; 48; z; 3F; 2L; 3E; 4E
Starting value.
Ending value.
How many bytes to generate?
Separate random bytes with this value. (Space by default.)
Custom Base
If you selected a custom base, set its value here. Valid bases are from 2 to 64.

How Does This Random Byte Generator Work?

This random byte generator works entirely in your browser and is written in JavaScript. To create a single random byte, it calls the Math.random() * 256 function. This creates a random floating point number in the range from 0 to 255. Next, this floating point number is converted to an integer by calling parseInt(byte, 10) function. Then, it uses the toString(base) function to convert this byte to the selected base (set in options). It fills the output_array with these bytes until its length is equal to the count (specified in options). Finally, all random bytes get displayed in the browser by using the join(separator) function, where separator is the symbol that gets put between bytes (also specified in options).

Created by Browserling

This random byte 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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