Convert octal to decimal
Each octal position holds a power of eight.
To convert octal to decimal, multiply each digit by the weight of its position.
Add the parts. The octal value 454 gives 300.
Try octal to decimal conversion in the bit editor
The octal value 454, which is 300. Edit the expression or select a bit to flip it.
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300
value · 16 bits · unsigned
- octal
- 0o454
Octal to decimal conversion step by step
Multiply each octal digit by the weight of its position: The steps follow the value above.
- Digit 4 at position 2: 4 x 64 = 256
- Digit 5 at position 1: 5 x 8 = 40
- Digit 4 at position 0: 4 x 1 = 4
- Add the parts. The total is 300.
The weight of each octal position
| Position | Weight | Decimal value |
|---|---|---|
| 0 | 8^0 | 1 |
| 1 | 8^1 | 8 |
| 2 | 8^2 | 64 |
| 3 | 8^3 | 512 |
| 4 | 8^4 | 4096 |
| 5 | 8^5 | 32768 |
Where octal to decimal conversion is used
A permission of 755 is a value a script has to compare as a number.
A legacy log that prints octal needs a conversion before any arithmetic.
A field of three bits reads directly as one octal digit.
Octal to decimal conversion: points to note
- The digits 8 and 9 do not exist in octal. A value with either digit is not octal.
- The octal value 10 is 8 in decimal. Do not read an octal value as decimal.
- A zero at the front marks octal in C, so 0755 is 493 in decimal.
- Beetwise holds one value in every base at the same time, so the decimal field shows the answer.
The full bit editor
The full editor holds many values, evaluates expressions across them, and reads live values from a serial port.
Open this value in the full editorQuestions about octal to decimal conversion
- What is 454 in octal as a decimal value?
- The octal value 454 is 300, because 4 x 64 plus 5 x 8 plus 4 gives 300.
- What is 755 in decimal?
- The octal value 755 is 493. It is the common permission for an executable file.
- Is octal still in use?
- Yes. Unix permissions, some assemblers and some legacy formats all use octal.