About

Web developers and system programmers often move between human-readable base-10 integers and machine-oriented hexadecimal values. Whether you are calculating CSS color codes (e.g., RGB values 0-255) or debugging memory offsets, this conversion is daily routine. A critical feature of this tool is the correct handling of negative numbers using Two"s Complement representation, mimicking how CPUs store signed integers in memory.

The interface allows you to constrain the output to specific bit widths (8-bit, 16-bit, 32-bit), showing exactly how a number like -1 appears as FF, FFFF, or FFFFFFFF depending on the allocated storage.

Formulas

For positive integers, the conversion uses repeated division by 16.

x = q × 16 + r

Where r is the hex digit.

For negative integers (Two"s Complement) with bit-width n:

Hex = (x + 2ⁿ) mod 2ⁿ

Reference Data

Decimal	Hex (8-bit)	Hex (16-bit)	Use Case
0	00	0000	Zero
10	0A	000A	LF (Line Feed)
127	7F	007F	Max signed 8-bit
255	FF	00FF	Max unsigned 8-bit / White (RGB)
-1	FF	FFFF	Two"s Complement
4096	Overflow	1000	Page size
65535	Overflow	FFFF	Max unsigned 16-bit port

Frequently Asked Questions

We use Two"s Complement logic. For example, -1 in 8-bit is calculated as 256 - 1 = 255 (FF).

Hexadecimal representations of negative numbers depend on the container size. -5 looks different in a Byte (FB) vs an Integer (FFFFFFFB).

Yes. Set the Bit Width to 8-bit. Enter your R, G, or B value (0-255) to get the 2-digit hex code.

The tool supports large integers up to 2^64 (64-bit unsigned), covering all standard computing data types.