gettype()

Introduction

PHP is a dynamically typed language: a variable's type is decided at runtime, not declared up front. The built-in gettype() function lets you inspect that type at runtime, returning a human-readable string such as "integer" or "string". It is handy when you are debugging unexpected values, branching on the type of a mixed input, or writing log messages that describe what you actually received.

This page covers the function's syntax, the exact strings it can return, the legacy type-name quirks that trip people up, and when to reach for gettype() versus the dedicated is_* functions.

Syntax

gettype(mixed $value): string

gettype() takes a single argument, $value — the variable whose type you want to know — and returns a string naming that type. It never throws and never modifies its argument.

Return values

gettype() returns one of a fixed set of strings:

Basic example

Example of PHP gettype()

Here we define four variables of different types and ask gettype() to name each one. The output is string, integer, boolean, and array — one type name per line.

The "double" and "integer" gotcha

The strings gettype() returns do not match the keywords you use in type declarations. A float is reported as "double", and an int is reported as "integer":

<?php
echo gettype(3.14), "\n"; // double  (NOT "float")
echo gettype(7),    "\n"; // integer (NOT "int")
echo gettype(null), "\n"; // NULL    (uppercase)
?>

Because of this, comparing gettype() output against "float" or "int" silently fails. If you only need a yes/no answer about a single type, prefer the dedicated functions — is_int(), is_float(), is_string(), is_array(), and friends — which are both faster and free of the naming surprise:

<?php
$value = 7;

// Brittle: depends on the legacy name
if (gettype($value) === "integer") { /* ... */ }

// Clearer and faster:
if (is_int($value)) { /* ... */ }
?>

On PHP 8.0 and later, get_debug_type() is the modern alternative: it returns the canonical names (int, float, bool) and, for objects, the actual class name instead of just "object".

When to use gettype()

• Debugging and logging — printing the type of a value alongside its content while tracking down a bug.
• Generic handling of mixed input — branching in a switch when a function legitimately accepts several types.
• Quick inspection — a one-off check at the console without caring about the modern naming.

For full structured dumps of a value (its type and its contents, recursively), use var_dump() or print_r(). To change a variable's type rather than read it, see settype(). For a broader tour of PHP's type system, read PHP Data Types.

Conclusion

gettype() gives you a quick, string-based answer to "what type is this value?" — useful for debugging, logging, and handling mixed input. Just remember the legacy names ("double" for floats, "integer" for ints) and reach for the is_* functions or get_debug_type() when you need a precise, future-proof check.

Practice