Hex to octal converter
Enter a hex number and get its octal value instantly, plus the other bases and the step-by-step working. Handles huge numbers, negatives and fractions.
Working for 7E316
Multiply each digit by its place value
- 7 × 16^27 × 256= 1792
- E (14) × 16^114 × 16= 224
- 3 × 16^03 × 1= 3
Add them up: 2019 in decimal.
Divide by 8, keep the remainders
- DivisionQuotientRemainder
- 2019 ÷ 82523
- 252 ÷ 8314
- 31 ÷ 837
- 3 ÷ 803
Read the remainders from the bottom up: 3743.
How to convert hex to octal
- Expand each hex digit to 4 bits.
- Regroup the bits in threes from the right and convert each group to an octal digit.
- FF = 1111 1111 → 011 111 111 = 377.
Hex is the shorthand for bytes: colour codes (#FF8800), memory addresses, MAC addresses, Unicode code points and hash digests are all written in it. Octal survives mainly in Unix file permissions (chmod 755), in some older systems, and in C/Python literals such as 0o755.
Related conversions
Binary to octal · Octal to hex · Decimal to octal · Hex to binary · Hex to decimal · any base 2–36 · signed (two's complement)
Questions people ask
How do you convert hex to octal?
Expand each hex digit to 4 bits. Regroup the bits in threes from the right and convert each group to an octal digit. FF = 1111 1111 → 011 111 111 = 377.
What is 7E3 in octal?
7E3 in hex (base 16) is 3743 in octal (base 8).
Does it handle negative numbers and fractions?
Yes. A leading minus sign is kept, and digits after a point are converted too. Some fractions that end in one base repeat forever in another (0.1 in decimal is 0.000110011… in binary), so the result is cut at 24 digits and marked as repeating.
Is there a size limit?
No practical one. The converter uses arbitrary-precision integers (JavaScript BigInt), so 64-bit, 128-bit and longer values convert exactly, without rounding.
Why is there no arithmetic in the working?
Every hex digit maps to a fixed group of bits, so conversion is a lookup rather than a calculation.