Hex to Decimal Converter

How to Convert Hex to Decimal

Converting hexadecimal to decimal uses positional notation — the same principle behind how decimal numbers work, but with base 16 instead of base 10. Each digit in a hex number has a positional value that is a power of 16, and the decimal result is the sum of all digit values multiplied by their positional weights.

The Positional Notation Formula

For a hex number with n digits, the formula is:

D = d(n-1) × 16^(n-1) + d(n-2) × 16^(n-2) + ⋯ + d(1) × 16^1 + d(0) × 16^0

Where d(i) is the decimal value of the hex digit at position i (counting from the right, starting at 0). Hex letters map to: A=10, B=11, C=12, D=13, E=14, F=15.

Step-by-Step Conversion Method

1. Write down the hex number — Remove any prefix such as 0x or #. For example, 0x1A3F becomes 1A3F.
2. Assign powers of 16 from right to left — The rightmost digit gets 16⁰ = 1, the next 16¹ = 16, then 16² = 256, 16³ = 4,096, and so on.
3. Convert hex letters (A–F) to their decimal values — Replace A with 10, B with 11, C with 12, D with 13, E with 14, and F with 15. Digits 0–9 remain unchanged.
4. Multiply each digit by its power of 16 — Calculate the product of each digit's decimal value and its corresponding power of 16.
5. Sum all products — Add all the products together. The result is the decimal equivalent.

Powers of 16 Reference

Power	Value	Meaning
16⁰	1	Ones place
16¹	16	Sixteens place
16²	256	Two-fifty-sixes place
16³	4,096	Four-thousand-ninety-sixes place
16⁴	65,536	16-bit boundary
16⁸	4,294,967,296	32-bit boundary

Hex to Decimal Conversion Table (00–FF)

This complete table covers all 256 byte values from 00 to FF. Each row shows the hexadecimal value, its decimal equivalent, 8-bit binary representation, and octal equivalent.

Quick Reference — Single Hex Digits 0–F:

Hex	Decimal	Binary	Octal
00	0	00000000	000
01	1	00000001	001
02	2	00000010	002
03	3	00000011	003
04	4	00000100	004
05	5	00000101	005
06	6	00000110	006
07	7	00000111	007
08	8	00001000	010
09	9	00001001	011
0A	10	00001010	012
0B	11	00001011	013
0C	12	00001100	014
0D	13	00001101	015
0E	14	00001110	016
0F	15	00001111	017

The full 00–FF table (256 entries) is available in the interactive converter above — use it to look up any byte value instantly.

This table covers all possible single-byte hexadecimal values (00–FF) with their decimal, 8-bit binary, and octal equivalents. For values beyond FF, apply the same positional notation formula to each hex digit.

Hex to Decimal Conversion Examples

Below are worked examples showing the hex to decimal conversion process step by step.

Convert 2F to Decimal

Hex: 2F

2 × 16¹ = 2 × 16 = 32
F (15) × 16⁰ = 15 × 1 = 15
32 + 15 = 47

Result: 2F₁₆ = 47₁₀

Convert FF to Decimal

Hex: FF

F (15) × 16¹ = 15 × 16 = 240
F (15) × 16⁰ = 15 × 1 = 15
240 + 15 = 255

Result: FF₁₆ = 255₁₀  (maximum value of an unsigned byte)

Convert 1A3F to Decimal

Hex: 1A3F

1 × 16³ = 1 × 4096 = 4096
A (10) × 16² = 10 × 256 = 2560
3 × 16¹ = 3 × 16 = 48
F (15) × 16⁰ = 15 × 1 = 15
4096 + 2560 + 48 + 15 = 6719

Result: 1A3F₁₆ = 6,719₁₀

Convert DEADBEEF to Decimal

DEADBEEF is a famous "hexspeak" debug marker used to mark uninitialized memory.

Hex: DEADBEEF

D (13) × 16⁷ = 13 × 268,435,456 = 3,489,660,928
E (14) × 16⁶ = 14 × 16,777,216 = 234,881,024
A (10) × 16⁵ = 10 × 1,048,576 = 10,485,760
D (13) × 16⁴ = 13 × 65,536 = 851,968
B (11) × 16³ = 11 × 4,096 = 45,056
E (14) × 16² = 14 × 256 = 3,584
E (14) × 16¹ = 14 × 16 = 224
F (15) × 16⁰ = 15 × 1 = 15

Result: DEADBEEF₁₆ = 3,735,928,559₁₀

Convert Color Code #3A7BD5 to Decimal

CSS hex color codes encode RGB channel values as pairs of hex digits.

Full value: 3A7BD5₁₆ = 3,833,813₁₀

Per channel (each pair is one byte):
  Red:   3A₁₆ = 3 × 16 + 10 = 58
  Green: 7B₁₆ = 7 × 16 + 11 = 123
  Blue:  D5₁₆ = 13 × 16 + 5 = 213

RGB result: (58, 123, 213) — a shade of blue

Hex to Decimal in Programming

Most programming languages provide built-in functions for hex-to-decimal conversion.

Python

# Convert hex string to decimal integer
hex_value = "FF"
decimal_value = int(hex_value, 16)
print(decimal_value)          # 255

# Using 0x prefix literal
value = 0xFF
print(value)                  # 255

# Decimal to hex (reverse)
print(hex(255))               # '0xff'
print(format(255, 'X'))       # 'FF'

# Large hex values
big_hex = "DEADBEEF"
big_decimal = int(big_hex, 16)
print(big_decimal)            # 3735928559

JavaScript

// Convert hex string to decimal number
const hexValue = "FF";
const decimalValue = parseInt(hexValue, 16);
console.log(decimalValue);    // 255

// Using 0x prefix literal
const value = 0xFF;
console.log(value);           // 255

// Decimal to hex (reverse)
console.log((255).toString(16).toUpperCase()); // 'FF'

// For values larger than 2^53, use BigInt
const bigHex = "DEADBEEFDEADBEEF";
const bigDec = BigInt("0x" + bigHex);
console.log(bigDec.toString()); // '16045690984833335023'

C

#include <stdio.h>
#include <stdlib.h>

int main() {
    // Convert hex string to decimal using strtol
    const char *hexStr = "FF";
    long decimal = strtol(hexStr, NULL, 16);
    printf("%ld\n", decimal);  // 255

    // Using hex literal
    int value = 0xFF;
    printf("%d\n", value);     // 255

    // Larger value
    unsigned long big = strtoul("DEADBEEF", NULL, 16);
    printf("%lu\n", big);      // 3735928559

    return 0;
}

Applications of Hex to Decimal Conversion

• Memory addresses — Debugging tools display memory addresses in hex (e.g., 0x7FFF5FBFF8AC). Converting to decimal helps with offset calculations and pointer arithmetic.
• Web color codes — CSS hex colors like #FF5733 encode RGB channel values as decimal 0–255. Converting hex pairs to decimal reveals the actual color intensity: FF = 255 (max red), 57 = 87 (moderate green), 33 = 51 (low blue).
• MAC addresses — Network interface identifiers (00:1A:2B:3C:4D:5E) use hex notation. Converting to decimal is needed for certain network administration tasks and database queries.
• Unicode code points — Characters are identified by hex code points (e.g., U+0041 for the letter "A"). Converting U+0041 to decimal gives 65, which is the ASCII value.
• Cryptographic hashes — Hash values like SHA-256 are displayed in hex. Converting individual bytes to decimal is useful for checksum verification and statistical analysis.

Related Converters

• Hex to Binary Converter — Convert hexadecimal numbers to binary with 4-bit group visualization
• Hex to RGB Converter — Convert hex color codes to RGB values for web design
• Hex to Text Converter — Decode hexadecimal strings into readable ASCII text
• Binary to Decimal Converter — Convert binary numbers to decimal representation
• Binary to Octal Converter — Convert binary numbers to octal (base-8) values