PHP intval() Function: Usage and Examples

Use intval() when you need to converts a value to an integer, optionally using a base for numeric strings in a PHP application. The examples below show the actual operation and its limitations.

What Is intval() in PHP?

Converts a value to an integer, optionally using a base for numeric strings. The exact signature supported by your installation depends on its PHP version and enabled extensions.

Its syntax is:

intval(mixed $value, int $base = ...): int

Parameters and return value: The parameter types, optional arguments, references, and return type are shown in the signature above. Optional parameters are marked with an ellipsis in this reference signature.

Example 1: Basic Usage

<?php

echo intval("42");

Output:

42

Example 2: Different Input or Behavior

<?php

echo intval("FF",16);

Output:

255

Practical Example: Applying the Function

<?php

$submittedQuantity = "12"; $quantity = filter_var($submittedQuantity,FILTER_VALIDATE_INT); echo $quantity === false ? "Invalid" : "Quantity: " . $quantity;

Output:

Quantity: 12

Important Behavior and Edge Cases

intval() performs conversion, not input validation; malformed strings may become zero.

Comparison With Related Functions

Common Beginner Mistakes

Key Takeaways

• Converts a value to an integer, optionally using a base for numeric strings.
• intval() performs conversion, not input validation; malformed strings may become zero.
• filter_var() with FILTER_VALIDATE_INT validates a complete integer representation.

Use intval() for the specific operation demonstrated above. Check its prerequisites and handle failure conditions before using it with production data.