The decimal number system uses base 10. It has ten digits, 0 through 9, and each place shows a power of 10. We use decimal numbers for everyday counting, money, and measurements.
The octal number system uses base 8. It has eight digits, 0 through 7, and each place shows a power of 8. Octal often appears in computing and number system lessons.
Our Decimal to Octal Converter quickly changes a decimal number into its matching octal value. Enter a number, view the result, and copy it for homework, coding, or study.
Type or paste the decimal number you want to convert.
Get the octal value instantly from your decimal number.
Copy the converted octal value for future use.
Type or paste the decimal number you want to convert.
Get the octal value instantly from your decimal number.
Copy the converted octal value for future use.
To convert a decimal number to octal, divide it by 8 and record each remainder. Keep dividing the quotient until it reaches 0. Then read the remainders upward. Formula: .
Step by step Guide
Practical Example
Convert 25 to octal. remainder . Next, remainder . Read upward: . Therefore, .
Decimal | Octal |
|---|---|
0 | 0 |
1 | 1 |
2 | 2 |
3 | 3 |
4 | 4 |
5 | 5 |
6 | 6 |
7 | 7 |
8 | 10 |
9 | 11 |
10 | 12 |
11 | 13 |
12 | 14 |
13 | 15 |
14 | 16 |
15 | 17 |
16 | 20 |
Note: Octal uses digits 0 through 7 only. If your answer contains 8 or 9, repeat the division and check every remainder before using the result.
Common Mistakes When Converting Decimal to Octal
Common errors include using 8 or 9 as an octal digit, forgetting a remainder, or reading remainders in the wrong order. Always divide by 8, keep every remainder, and read the final remainders from bottom to top. Then verify the result by converting it back to decimal.
These FAQs explain the octal base, common uses, simple conversions, valid digits, and ways to convert decimal numbers by hand.