Binary Converter
Convert numbers between binary, octal, decimal and hexadecimal (or any base 2–36), and text to binary and back. Exact for very large numbers. Free.
- Binary
1111 1111- Octal
377- Hexadecimal
FF- Bits
- 8
Number bases and binary text
Computers store everything as binary (base 2): 255 in decimal is 11111111 in binary and FF in hexadecimal (base 16), which programmers use as a compact way to write bytes. Enter a number in any base from 2 to 36 and see it in binary, octal, decimal and hex at once; numbers of any size stay exact. Switch to Text ↔ binary to turn text into its UTF-8 bytes written in binary, or paste 8-bit groups like 01001000 01101001 to read them back as text.
How to use it
- 1
Choose numbers or text
Convert between bases, or between text and binary.
- 2
Enter the value
And pick the base it's written in.
- 3
Read every base
Binary is grouped in fours for easier reading.
Frequently asked questions
How do I convert binary to decimal?
Add the place values of each 1, from 1 on the right doubling each step. 1011 = 8 + 0 + 2 + 1 = 11.
Why do programmers use hexadecimal?
One hex digit is exactly four bits, so a byte is always two hex digits (00 to FF), shorter and easier to read than eight binary digits.
How is text turned into binary?
Each character is encoded as UTF-8 bytes, and each byte is written as 8 binary digits. 'H' is 01001000.
Is anything sent to a server?
No. Everything is calculated in your browser.