PHP Program for Binary to Decimal Conversion

Binary to decimal conversion is the process of converting a binary number (base-2 number using only 0s and 1s) into its equivalent decimal number (base-10 form).

In this article, we will learn how to convert binary numbers to decimal form in PHP using different approaches.

How Binary to Decimal Conversion Works

To convert a binary number to decimal, multiply each binary digit by 2 raised to the power of its position (starting from 0 on the right), then sum all results ?

Method 1: Using Built-in bindec() Function

PHP provides the bindec() function to convert binary numbers directly to decimal ?

<?php
$binary = "101";

// Convert binary to decimal using bindec()
$decimal = bindec($binary);

echo "Binary $binary = Decimal $decimal";
?>

Binary 101 = Decimal 5

Method 2: Manual Conversion Using Loop

This approach manually calculates the decimal value by iterating through each binary digit ?

<?php
$binary = "1011";
$decimal = 0;
$length = strlen($binary);

// Loop through each digit from right to left
for ($i = 0; $i < $length; $i++) {
    $digit = $binary[$length - $i - 1];
    $decimal += $digit * pow(2, $i);
}

echo "Binary $binary = Decimal $decimal";
?>

Binary 1011 = Decimal 11

Method 3: Using Bitwise Left Shift

This method uses bitwise operations for efficient conversion ?

<?php
function binaryToDecimalBitwise($binary) {
    $decimal = 0;
    for ($i = 0; $i < strlen($binary); $i++) {
        $decimal = ($decimal << 1) + $binary[$i];
    }
    return $decimal;
}

$binary = "1111";
$decimal = binaryToDecimalBitwise($binary);

echo "Binary $binary = Decimal $decimal";
?>

Binary 1111 = Decimal 15

Comparison of Methods

Conclusion

Use bindec() for simple binary to decimal conversions in PHP. For educational purposes or custom logic, implement manual conversion using loops or bitwise operations.