Binary & Hex Converter

Convert binary, decimal, and hexadecimal while reading IoT bytes and registers

Interactive animation Number systems IoT debugging

Binary & Hex Converter

Turn one IoT value into decimal, hexadecimal, and binary. Then inspect each bit so raw sensor bytes, GPIO registers, and protocol headers become readable instead of mysterious.

165Unsigned decimal

0xA5Hexadecimal

0, 2, 5, 7HIGH bit positions

Goal

Read raw IoT numbers without guessing what each digit means.

Try

Load the GPIO example, then click the bit cells that are HIGH.

Watch

One hex digit maps to exactly four binary bits.

Apply

Use the scenario cards to decode sensor bytes and protocol headers.

Converter Setup

Input Value valid

Use prefixes if helpful: 0xA5 or 0b10100101.

Input Base hex Hexadecimal Decimal Binary

Word Width 8 bits 8 bits / 1 byte 16 bits / 2 bytes 32 bits / 4 bytes

Show signed interpretation

Live Numbers

Unsigned

165

Signed

-91

Hex

0xA5

Binary

1010 0101

Selected Bit

bit 0 = 1

Weight

1

Number Conversion Animation

The same value is shown in three number systems. Step through the process to see why hex is a compact way to write binary bytes.

Normalize

1. Normalize inputClean prefixes and choose the base.

2. Fit the wordClamp to the selected bit width.

3. Map nibblesEach hex digit maps to four bits.

4. Read meaningApply it to sensors, registers, or packets.

normalize

Decimal

165

Hexadecimal

0xA5

Binary

1010 0101

Bit Visualizer

Bit 0 is the least significant bit on the right. Click any bit to inspect its place value.

8-bit word

GPIO register 0xA5 means bits 0, 2, 5, and 7 are HIGH. That is easier to see as binary 1010 0101.

Sensor Byte

0x7F is 127 unsigned. As an 8-bit signed value, it is still +127.

GPIO Register

0xA5 is 1010 0101, so pins 0, 2, 5, and 7 are HIGH.

MQTT Header

0x10 is the MQTT CONNECT fixed header byte: type 1 with flags 0.

Learning Support

Beginner Model

Binary uses base 2, decimal uses base 10, and hexadecimal uses base 16. They can all describe the same stored value.

Hex Shortcut

One hex digit equals one nibble, which is four bits. Two hex digits make one byte, so 0xA5 becomes 1010 0101.

Common Mistakes

• Reading bit 0 from the left instead of the right.
• Mixing signed and unsigned interpretations.
• Forgetting that a fixed width controls overflow.

Quick Reference

Decimal	Hex	Binary	Typical IoT Meaning
0	0x00	0000 0000	all flags off, null byte
16	0x10	0001 0000	MQTT CONNECT fixed header byte
127	0x7F	0111 1111	maximum signed 8-bit positive value
128	0x80	1000 0000	minimum signed 8-bit negative value
165	0xA5	1010 0101	alternating GPIO flags
255	0xFF	1111 1111	all 8-bit flags on, unsigned byte maximum
1023	0x03FF	0000 0011 1111 1111	10-bit ADC maximum count
4095	0x0FFF	0000 1111 1111 1111	12-bit ADC maximum count