Developer Tools
Decimal to Binary Converter
Type any whole number and get the binary equivalent instantly. The division-by-2 steps are shown so you can follow along.
Convert decimal to binary in three steps
No software to install. Works in any browser, on any device.
Enter a decimal number
Type any whole number.
See the binary output
The binary representation appears instantly.
Copy the result
Click to copy the binary string.
Division steps
Instant conversion
Binary output updates as you type each digit.
Shows the method
See the repeated division steps so you can learn the algorithm.
Any integer
No size limit — convert any whole number.
About Decimal to Binary Conversion
Every decimal number has an exact binary representation. The standard method is repeated division by 2: divide your number by 2, note the remainder, then repeat with the quotient until you reach 0. Read the remainders from bottom to top and you have the binary number.
For example, 214 in decimal is 11010110 in binary — 8 bits, which fits in a single byte.
Understanding decimal-to-binary conversion has real practical value. File permissions in Unix/Linux are set using octal numbers, which map directly to binary triplets. Subnet masks in networking are binary patterns — 255.255.255.0 is 11111111.11111111.11111111.00000000. Bitwise operations in code (AND, OR, XOR, NOT) all work on the binary representations of numbers.
The tool also shows the hexadecimal (base 16) and octal (base 8) equivalents. Hex is particularly compact because every four binary digits map to exactly one hex digit — making it the format used for colour codes, memory addresses, and encoding.
Need the reverse? Binary to Decimal → · Other tools: Base64 Encoder/Decoder · JSON Formatter
More Developer Tools
Binary to Decimal
Paste a binary string and see the decimal value with a positional breakdown.
Use itBase64 Encoder/Decoder
Encode text to Base64 or decode a Base64 string back to plain text.
Use itJSON Formatter
Beautify and validate JSON. Catch syntax errors instantly.
Use itFrequently Asked Questions
How do you convert decimal to binary?
Repeatedly divide by 2 and record the remainder. Read remainders from bottom to top. For 13: 13÷2=6 r1, 6÷2=3 r0, 3÷2=1 r1, 1÷2=0 r1 → read bottom to top: 1101.
What is 255 in binary?
11111111 — eight 1s. The maximum value of an 8-bit unsigned byte.
How many bits does it take to represent 1000?
1000 = 1111101000 — 10 bits. Bits needed = ⌈log₂(n+1)⌉.
Binary vs hexadecimal?
Binary is base-2 (digits 0-1). Hex is base-16 (0-9, A-F). One hex digit represents exactly 4 binary digits. FF hex = 11111111 binary = 255 decimal.