Binary to Hex Converter

Convert numbers between binary, decimal, hexadecimal and octal. For reading register values, understanding color codes, setting pin configurations, or debugging Arduino and ESP32 code.

Last updated: May 2026

Enter a value to see the conversion instantly.

How to use this number base converter

Type your number in any base and see it in all other bases instantly. The quick buttons show 11111111 in binary (8 bits all high), 255 in decimal (max value for 8-bit unsigned), FF in hex (same value, compact notation), and 377 in octal (less common but still used in some embedded systems).

Common number base reference values

DecimalBinaryHexadecimalOctalCommon use
000000x00GPIO pin LOW
100010x11GPIO pin HIGH
1511110xF174-bit nibble max
255111111110xFF3778-bit byte max / RGB color max
102311111111110x3FF177710-bit ADC max value
40951111111111110xFFF777712-bit ADC/DAC max
6553511111111111111110xFFFF17777716-bit unsigned max

When you need this tool

Your ESP32 datasheet shows register values like 0x3FF but your code expects decimal. Or you're setting RGB LED colors where the web designer sends you #FF5733 but your microcontroller wants three separate 0-255 values. Or you're debugging I2C communication and the logic analyzer shows binary 10110010 but the device address is listed as 0xB2. Enter any number in any base and see it in all others instantly.