About the Hex to Octal
Hex and octal do not line up the way hex and binary do. A hex digit carries four bits while an octal digit carries three, so there is no digit for digit shortcut between them. The reliable route is to expand the hex into bits, regroup those bits into triples from the right, and read the triples back as octal. This page does that internally with arbitrary precision integers, so a 64 character hex string converts without losing a single low bit.
Input is case insensitive and an optional 0x prefix is stripped. Internal spaces, underscores and commas are ignored, which means a MAC address style value such as 1A,3F or a spaced memory dump line still parses. A character outside 0 to 9 and A to F halts the conversion with an explicit message rather than silently truncating the value, which is the usual failure mode of naive converters that lean on floating point.
The result can be spaced in threes, prefixed with 0o, or printed beside its source value for a side by side audit trail. Appending the reference table gives you the sixteen hex digits with their octal equivalents for spot checks. Hex remains the default for memory addresses and colour codes while octal survives mainly in Unix permissions, so this conversion usually appears when porting old code. The reverse trip is Octal to Hex, and every base at once is available in the All Base Converter.
How to use
- Paste the hexadecimal values into the left pane, one per line.
- Leave the
0xprefixes in place if you have them; they are stripped automatically. - Tick Show source value to print each hex value beside its octal form.
- Copy or download the octal column.
Common questions
- Why is there no direct hex digit to octal digit mapping?
- A hex digit covers four bits and an octal digit covers three. Four is not a multiple of three, so the digit boundaries never line up.
- Can it convert very long hex strings?
- Yes. Values are parsed as arbitrary precision integers, so a hash or a 256-bit key converts exactly.
- Is the input case sensitive?
- No. Upper and lower case hex digits are treated identically, so DEADBEEF and deadbeef give the same octal.
- What if my value has a trailing h suffix?
- Remove it first. Only a leading 0x prefix is recognised; a trailing h is reported as an invalid character.