Decimal to Hex Converter

Convert decimal (base 10) numbers to hexadecimal (base 16)

Hexadecimal Result

0xFF

or just: FF

Division Method Steps

StepDivisionQuotientRemainderHex Digit
1255 / 161515F
215 / 16015F

Read hex digits from bottom to top: FF

Common Decimal Values

Common Uses

• Color codes in CSS (e.g., #FF5733)

• Memory addresses in programming

• MAC addresses in networking

• Unicode code points (e.g., U+1F600)

Decimal to Hexadecimal Conversion

Decimal to hexadecimal conversion transforms a base 10 number into a base 16 representation using the digits 0-9 and letters A-F. Hexadecimal is the most commonly used non-decimal number system in computing, providing a concise way to represent binary data. Each hex digit corresponds to exactly four binary bits, so a byte — the fundamental unit of digital data — is always represented by exactly two hex digits.

The hexadecimal system is preferred in many computing contexts because of its direct relationship to binary. While decimal requires conversion through powers of 10, hex aligns naturally with the binary structure of computer data. A 32-bit integer, for example, is eight hex digits, making it easy to read and manipulate. This alignment makes hex the standard notation for memory addresses, color values, error codes, and data formats.

This calculator converts any non-negative decimal integer to hexadecimal using the repeated division method. It shows each step of the process — dividing by 16, recording the remainder, and mapping the remainder to the appropriate hex digit. The result is displayed with the standard 0x prefix used in most programming languages to indicate hexadecimal notation.

The Division Method

The conversion uses repeated division by 16, where each remainder corresponds to a hex digit. The remainders, read in reverse order, form the hexadecimal number.

Decimal to Hex Division

Hex = Reverse(Decimal % 16 mapped to hex digit, Decimal ÷ 16, ...)

Where:

  • Decimal= The base 10 number to convert
  • % 16= Remainder when divided by 16 (0-15)
  • ÷ 16= Integer division by 16 for the next step

How the Steps Work

The conversion begins with the decimal number. Divide it by 16 and note the remainder — this becomes the least significant hex digit (rightmost). Take the quotient and divide by 16 again, noting the new remainder. Continue until the quotient is zero. The hex result is the sequence of remainders read from last to first.

For remainders 0 through 9, the hex digit is the same as the decimal digit. For remainders 10 through 15, the hex digits are A through F respectively. This mapping is consistent and unambiguous. For example, converting decimal 255: 255 ÷ 16 = 15 remainder 15 (F), then 15 ÷ 16 = 0 remainder 15 (F), giving hex FF.

The calculator also shows the binary and octal equivalents alongside the hex result, giving you a complete picture of how the same number is represented in different bases. This is particularly useful for understanding the relationships between number systems.

How to Use This Calculator

The decimal to hex calculator provides a thorough conversion experience:

  1. Enter a decimal number: Type any non-negative integer into the input field.
  2. View the hex result: The hexadecimal value appears with the 0x prefix, showing the standard programming notation.
  3. See all bases: The binary and octal equivalents are displayed alongside hex for comparison.
  4. Study the steps: The division method table shows each step with the dividend, quotient, remainder, and hex digit.
  5. Use quick values: Preset buttons let you explore common values like 255 (FF), 256 (100), and 65535 (FFFF).

Real-World Applications

Hexadecimal is essential for web development and CSS colors. Every CSS color defined in hex notation uses six digits to represent RGB values. Understanding how decimal 255 becomes hex FF helps developers manipulate colors programmatically. A color like #336699 uses hex values that are easier to remember and compare than their decimal equivalents (51, 102, 153).

In embedded systems and IoT, hardware registers and peripherals are addressed using hexadecimal. Configuration values, bitmask operations, and protocol data are standardly expressed in hex. Engineers working with microcontrollers, sensors, and communication interfaces like I2C, SPI, and UART routinely convert between decimal and hex when writing firmware.

Error debugging often involves interpreting hex values from crash logs, memory dumps, and network captures. Exception codes, stack addresses, and data payloads are frequently displayed in hex format. Being able to quickly convert hex to decimal and back helps developers diagnose issues and understand what went wrong during execution.

Worked Examples

Converting 42 to Hex

Problem:

What is the hexadecimal equivalent of decimal 42?

Solution Steps:

  1. 142 ÷ 16 = 2 remainder 10 → A
  2. 22 ÷ 16 = 0 remainder 2 → 2
  3. 3Read from last to first: 2A

Result:

42 in decimal = 0x2A in hexadecimal

Converting 1000 to Hex

Problem:

Convert decimal 1000 to hexadecimal.

Solution Steps:

  1. 11000 ÷ 16 = 62 remainder 8 → 8
  2. 262 ÷ 16 = 3 remainder 14 → E
  3. 33 ÷ 16 = 0 remainder 3 → 3

Result:

1000 in decimal = 0x3E8 in hexadecimal

Converting 65535 to Hex

Problem:

What is 65535 in hexadecimal?

Solution Steps:

  1. 165535 ÷ 16 = 4095 remainder 15 → F
  2. 24095 ÷ 16 = 255 remainder 15 → F
  3. 3255 ÷ 16 = 15 remainder 15 → F
  4. 415 ÷ 16 = 0 remainder 15 → F

Result:

65535 in decimal = 0xFFFF in hexadecimal (maximum 16-bit value)

Tips & Best Practices

  • Each hex digit is exactly 4 bits — use this for quick binary-to-hex conversion
  • 0xFF = 255 is the maximum byte value and the most important hex reference
  • Two hex digits always equal one byte, making hex ideal for compact binary display
  • The 0x prefix is standard in C, Python, JavaScript, and most programming languages
  • Colors in CSS use hex: #RRGGBB where each pair is a channel from 00 to FF
  • Memory addresses in debuggers are typically shown in hex for alignment clarity

Frequently Asked Questions

Both calculators perform the same core conversion from decimal to hexadecimal. This version shows the binary and octal equivalents alongside hex, and includes a hex digit reference table for learning. The converter version focuses more on the division method steps with detailed breakdowns. Choose whichever layout you prefer.
The hexadecimal system needs sixteen distinct symbols (0-15), but decimal digits only go from 0 to 9. To represent values 10 through 15, hex uses the letters A through F. This keeps the notation compact — each digit position still holds exactly one symbol, maintaining the positional notation system used by all standard number bases.
Each hex digit represents 4 bits. For an n-bit number, you need ceiling(n/4) hex digits. For common sizes: 8 bits = 2 hex digits (00-FF), 16 bits = 4 hex digits (0000-FFFF), 32 bits = 8 hex digits (00000000-FFFFFFFF). The number of hex digits needed equals ceiling(log₁₆(number + 1)).
Two hex digits can represent values from 0x00 (0) to 0xFF (255), giving 256 possible values. This corresponds to one byte of data. Since 16² = 256, two hex positions provide exactly enough range to represent every possible byte value, which is why hex is so closely tied to byte-oriented data.
While hexadecimal is primarily a computing notation, it occasionally appears in other fields. Some color systems outside of computing use hex notation. Historically, the Base-16 system was used in some traditional counting systems. However, its main application remains in computing for representing binary data in a compact, readable format.

Sources & References

Last updated: 2026-06-06

💡

Help us improve!

How would you rate the Decimal to Hex Converter?

<>

Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

Source

Formula Source: NIST Guide to SI Units

by National Institute of Standards

UpdatedLast reviewed: May 2026
CheckedFormula checks are based on standard references and internal QA review.