RandomNr

Random Octal Number Generator

Generate random octal values of the digit length you choose, with decimal shown alongside.

Random Octal Generator

5273 (2747)

6 digit octal

How many values

Length

Copy separator

How to use the octal generator

  1. Set how many octal digits you want.
  2. Generate one value or a batch, with the decimal shown alongside.
  3. Copy or export the values.

About Random Nr's Octal Number Generator

The random octal number generator produces octal values of the digit length you choose, with the decimal equivalent shown alongside. Set how many octal digits you want and how many values, and Random Nr draws each one and prints its decimal value too, which helps with low level programming work, file permissions and teaching number systems.

Where octal numbers are still used

Octal is base 8, using only the digits 0 to 7. Its main modern home is Unix file permissions, where three octal digits set read, write and execute for owner, group and others.

OctalPermissionsMeaning
755rwxr-xr-xowner full, others read and run
644rw-r--r--owner read and write, others read
777rwxrwxrwxeveryone full access
600rw-------owner only

Each octal digit is exactly three bits, which is why it maps so neatly onto the three permission flags. Read is 4, write is 2, execute is 1, so 7 is all three and 5 is read plus execute.

How octal relates to binary

The reason octal exists at all is that one octal digit stands for exactly three binary digits, so 111 in binary is 7 in octal. Before hexadecimal took over, that made octal the compact way to write binary on machines whose word sizes were multiples of three bits. Today hex, at four bits per digit, fits byte oriented hardware better, which is why octal is now mostly a permissions notation.

How to read octal values

Each octal value here is shown with its decimal equivalent in brackets, so you can read the base 8 string and know the plain quantity at once. To convert a specific value between octal and other bases, use the number base converter.

More math and sequence generators

Frequently asked questions

What is octal

Base 8, using the digits 0 to 7. Three bits map to one octal digit, which is why it appears in file permission codes.

Is the decimal value shown

Yes. Each octal value is followed by its decimal equivalent in brackets for easy reading.

What digit lengths can I use

From 1 to 64 octal digits, covering short codes and long values alike.

Can I make several

Yes, up to 500 at once, ready to copy or export.

Is it free

Yes, free and with no sign up.

Related generators

Convert a value to octal with the number base converter, or draw hex or binary.