PHP $_FILES

The FILES array is where PHP writes down all the details of files a visitor uploaded, like a receipt with the name, size, and where it is waiting. You read it to decide what to do with each file.

In this page:

Accessing File Name and Type
Checking Upload Sizes
Identifying Upload Errors
Retrieving Temporary Paths
Processing Multiple File Uploads

Syntax

php

$_FILES["field_name"]["name"];       // original file name
$_FILES["field_name"]["type"];       // MIME type
$_FILES["field_name"]["size"];       // bytes
$_FILES["field_name"]["tmp_name"];   // temporary path
$_FILES["field_name"]["error"];      // UPLOAD_ERR_OK (0) means success

Accessing File Name and Type

The $_FILES superglobal is a two-dimensional associative array — to access an uploaded file's original name or MIME type, use $_FILES[input_name][name] and $_FILES[input_name][type].

Example: Accessing File Name and Type

php

<?php
// Set `$_FILES['avatar']` to `['name' => 'pic.png', 'type' => 'image/png']`
$_FILES['avatar'] = ['name' => 'pic.png', 'type' => 'image/png'];
// Print `$_FILES['avatar']['name'] . " - " . $_FILES['avatar']['type']` to the output
echo $_FILES['avatar']['name'] . " - " . $_FILES['avatar']['type'];
?>

Checking Upload Sizes

The size key in $_FILES holds the file's size in bytes, and checking it against your project's limits before moving the file to a permanent directory avoids wasting disk space on oversized uploads.

Example: Checking Upload Sizes

php

<?php
$_FILES['avatar']['size'] = 3000000;
// Declare `$maxSize`, set to `2000000`
$maxSize = 2000000;
// Check whether `$_FILES['avatar']['size'] > $maxSize`
if ($_FILES['avatar']['size'] > $maxSize) {
    // Print "File too large" to the output
    echo "File too large";
}
?>

Identifying Upload Errors

The error key inside $_FILES holds a numeric code like UPLOAD_ERR_OK (0) — always check this value first, before touching any other metadata, to confirm the upload actually succeeded.

Example: Identifying Upload Errors

php

<?php
$_FILES['avatar']['error'] = UPLOAD_ERR_OK;
// Check whether `$_FILES['avatar']['error'] === UPLOAD_ERR_OK`
if ($_FILES['avatar']['error'] === UPLOAD_ERR_OK) {
    // Print "Upload OK, check other metadata now" to the output
    echo "Upload OK, check other metadata now";
}
?>

Retrieving Temporary Paths

When a file is uploaded, PHP stores it in a temporary directory, with its path saved under the tmp_name key — that temporary path is what you pass to move_uploaded_file() or use for validation.

Example: Retrieving Temporary Paths

php

<?php
$_FILES['avatar']['tmp_name'] = '/tmp/phpABC123';
// Print `"Temp path: " . $_FILES['avatar']['tmp_name']` to the output
echo "Temp path: " . $_FILES['avatar']['tmp_name'];
?>

Processing Multiple File Uploads

If a form supports multiple file uploads using array-style input names (like files[]), $_FILES returns nested arrays of values instead of single strings, so you loop through the indices to process each file individually.

Example: Processing Multiple File Uploads

php

<?php
// Set `$_FILES['files']` to `[`
$_FILES['files'] = [
    'name' => ['a.jpg', 'b.jpg'],
    'size' => [1000, 2000],
];
// Loop over `$_FILES['files']['name']`, binding each item to `$index => $name`
foreach ($_FILES['files']['name'] as $index => $name) {
    // Print "$name: " . $_FILES['files']['size'][$index] . " bytes\n" to the output
    echo "$name: " . $_FILES['files']['size'][$index] . " bytes\n";
}
?>

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