How to Get the Featured Image in WordPress (PHP Examples)

To get the featured image of a WordPress post with PHP, use one of three core functions depending on what you need. If you are chasing sizing rather than code, our guide to WordPress featured image size explains which registered size your theme is actually rendering:

// The full <img> tag (easiest, drop into the loop)
the_post_thumbnail( 'large' );

// Just the URL as a string
$url = get_the_post_thumbnail_url( get_the_ID(), 'large' );

// Just the attachment ID
$id = get_post_thumbnail_id( get_the_ID() );

Below I’ll cover all the common variations: displaying as a responsive <img> tag, grabbing just the URL for CSS or srcset, getting the attachment ID for advanced use, checking whether a post even has a featured image, getting any image by its ID, the REST API route, and a handful of edge cases (alt text, lazy loading, fallback images, custom image sizes).

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Before you start: make sure featured images are enabled

If the “Featured image” panel isn’t showing in the block editor, your theme hasn’t declared support for post thumbnails. Add this to your theme’s functions.php (or a child theme’s functions.php). It uses the after_setup_theme action hook to register support for post thumbnails:

add_action( 'after_setup_theme', function() {
    add_theme_support( 'post-thumbnails' );
} );

Most modern themes (including Hello Elementor, Twenty Twenty-Four, Kadence, and Astra) already enable this. You only need to add it when building a theme from scratch or using a stripped-down starter theme.

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Method 1: Display the featured image as an <img> tag

the_post_thumbnail() echoes a full <img> tag (with srcset, sizes, alt text, and proper classes baked in). Inside the loop, this is a one-liner:

// Inside the loop
if ( has_post_thumbnail() ) {
    the_post_thumbnail( 'large' );
}

// With custom attributes (class, alt override, etc.)
the_post_thumbnail( 'large', array(
    'class' => 'hero-image',
    'alt'   => esc_attr( get_the_title() ),
) );

Notice there is no loading attribute in that example. You will see 'loading' => 'lazy' in a lot of older snippets, and an earlier version of this one had it too. WordPress has added loading="lazy" to images automatically since 5.5, and since 6.3 it goes further: it leaves the first images on the page eager and gives the one it judges likely to be the Largest Contentful Paint a fetchpriority="high". Forcing lazy on a hero image overrides that and delays the biggest thing on the page. If you want to be explicit for an above-the-fold image, say the opposite:

// Above-the-fold hero: tell the browser it matters. Do not lazy-load it.
the_post_thumbnail( 'large', array(
    'class'         => 'hero-image',
    'loading'       => 'eager',
    'fetchpriority' => 'high',
) );

// Below the fold: leave loading out and let WordPress decide (lazy since 5.5).
the_post_thumbnail( 'medium_large', array( 'class' => 'card-image' ) );

Core respects what you pass: a loading value you supply is kept, and since 7.0 setting fetchpriority to low or auto also stops lazy-loading being added. For images below the fold, leave both attributes off and let WordPress handle them.

If you need the HTML as a string (to concatenate or pass around), use get_the_post_thumbnail() instead. Same arguments, but it returns the markup rather than echoing it.

$thumbnail_html = get_the_post_thumbnail( get_the_ID(), 'large' );
echo $thumbnail_html;

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Method 2: Get just the featured image URL

When you only need the URL (for a CSS background, an Open Graph tag, a custom image component, or a JSON API response), get_the_post_thumbnail_url() returns a plain string:

// Current post, large size
$url = get_the_post_thumbnail_url( get_the_ID(), 'large' );

// Specific post by ID, full size
$url = get_the_post_thumbnail_url( 42, 'full' );

// Inside the loop, default (post-thumbnail) size
$url = get_the_post_thumbnail_url();

echo esc_url( $url );

Returns false if the post has no featured image, so check for it before echoing. Available since WordPress 4.4 (2015), so effectively everywhere at this point.

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Method 3: Get the featured image ID

The featured image ID is just the attachment ID of the media library item WordPress is using. You need it when you want to call other WordPress functions that take an attachment ID (wp_get_attachment_image_src(), wp_get_attachment_metadata(), get_post_meta(), etc.):

$thumbnail_id = get_post_thumbnail_id( get_the_ID() );

// Example: get the image at an arbitrary size as an array
// Returns [ url, width, height, is_intermediate ]
$image = wp_get_attachment_image_src( $thumbnail_id, 'full' );
if ( $image ) {
    $url    = $image[0];
    $width  = $image[1];
    $height = $image[2];
}

// Example: read the image's alt text from the media library
$alt = get_post_meta( $thumbnail_id, '_wp_attachment_image_alt', true );

Returns 0 if there’s no featured image, and false if the post itself does not exist (since 5.5), so either check the return value or use has_post_thumbnail() first.

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Method 4: Check if a post has a featured image (with fallback)

has_post_thumbnail() returns a simple boolean. Use it to guard against empty states and to swap in a fallback image:

if ( has_post_thumbnail() ) {
    the_post_thumbnail( 'large' );
} else {
    // Fallback to a default image in your theme
    printf(
        '<img src="%s" alt="" loading="lazy" />',
        esc_url( get_template_directory_uri() . '/assets/default-featured.jpg' )
    );
}

Good rule: every template that displays a featured image should handle the “no image” case. Either a fallback, a different layout, or skipping the image container entirely. A broken <img> tag with no src is the worst outcome.

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Method 5: Use the featured image as a CSS background

For hero sections, card overlays, and anywhere a CSS background image is cleaner than an <img>, grab the URL and drop it into an inline style:

<?php
$featured_url = get_the_post_thumbnail_url( get_the_ID(), 'large' );

if ( $featured_url ) :
?>
    <section
        class="post-hero"
        style="background-image: url('<?php echo esc_url( $featured_url ); ?>');">
        <h1><?php the_title(); ?></h1>
    </section>
<?php endif; ?>

For multiple breakpoint sizes, use image-set() in your CSS with different sizes pulled via wp_get_attachment_image_src(). Don’t use full on a hero unless you actually want the original upload (often 2000px+ wide). Pick a size that matches the rendered container.

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Featured image sizes (and picking the right one)

Every featured image function accepts a size keyword as the second argument. The built-in sizes:

Size keyword	Default dimensions	Typical use
thumbnail	150 × 150 (cropped)	Small avatar-style lists
medium	300 × 300 max	Sidebar thumbnails
medium_large	768 × any	Card grids
large	1024 × 1024 max	Most post heroes
1536x1536	1536 × 1536 max	Wide heroes and srcset steps (since 5.3)
2048x2048	2048 × 2048 max	The largest generated size (since 5.3)
full	Original upload, or the 2560px scaled copy for big uploads	Only when you need the raw image
post-thumbnail	Theme-defined	Theme’s declared default size

The two oddly named sizes arrived with WordPress 5.3’s big-image handling. Anything you upload above 2560px is scaled down and that copy becomes full; 1536x1536 and 2048x2048 exist so srcset has sensible steps between large and that ceiling. Our guide to large image scaling covers the mechanism and how to change it.

You can also register custom sizes in functions.php:

add_action( 'after_setup_theme', function() {
    add_theme_support( 'post-thumbnails' );

    // Hard-cropped 1200x630 for social cards and hero images
    add_image_size( 'hero', 1200, 630, true );

    // Proportional 400-wide for card grids
    add_image_size( 'card', 400, 9999, false );
} );

After registering a new size, regenerate existing images with the Regenerate Thumbnails plugin or wp media regenerate via WP-CLI. New sizes only apply to images uploaded after the declaration.

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Get any image by its attachment ID

Everything above assumes the image is the post’s featured image. Often it is not: it is a logo stored in an option, a gallery item, or an ID saved in a custom field. All of those are attachments, and the featured-image functions are thin wrappers around the attachment functions, which you can call directly with any ID:

$attachment_id = 123; // any media library image, featured or not

// URL of a specific size (since 4.4). Returns false if the attachment does not exist.
$url = wp_get_attachment_image_url( $attachment_id, 'large' );

// URL of the original upload
$original = wp_get_attachment_url( $attachment_id );

// A complete <img> tag with srcset, sizes, alt and loading attributes
echo wp_get_attachment_image( $attachment_id, 'large', false, array( 'class' => 'gallery-item' ) );

wp_get_attachment_image_url() has been in core since 4.4 and is the one to reach for when you want a specific size; wp_get_attachment_url() always returns the original file. get_the_post_thumbnail_url() is literally wp_get_attachment_image_url( get_post_thumbnail_id( $post ), $size ), so once you have an ID from anywhere, the featured image stops being a special case.

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Get the featured image from the REST API

If you are building a headless front end, an app, or just poking at a site from a script, the featured image is available without any PHP. A post from /wp-json/wp/v2/posts carries the attachment ID in featured_media, and adding _embed pulls the image object into the same response:

GET /wp-json/wp/v2/posts/42?_embed=wp:featuredmedia

// In the JSON response:
_embedded["wp:featuredmedia"][0].source_url                        // the full (or scaled) image
_embedded["wp:featuredmedia"][0].media_details.sizes.large.source_url  // a specific size
_embedded["wp:featuredmedia"][0].alt_text                          // alt text

Without _embed, take the ID from featured_media and fetch /wp-json/wp/v2/media/{id}; the same source_url and media_details.sizes fields are on that object. The sizes listed there are exactly the registered sizes from the table above, including 1536x1536 and 2048x2048. A featured_media of 0 means the post has no featured image.

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Block themes: the Post Featured Image block

On a block theme the template work is done by the Post Featured Image block, which calls the same functions with a settings panel in front of them, including a link-to-post toggle, aspect ratio, and an override for the hero image’s size. The PHP on this page is still what you need inside plugins, custom blocks and classic theme templates.

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Frequently asked questions

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Bottom line

For display in the loop, the_post_thumbnail( 'large' ) is the one-liner to reach for. When you need the URL as a string, use get_the_post_thumbnail_url( $id, 'large' ). When you need the attachment ID for downstream calls, use get_post_thumbnail_id( $id ).

Always guard with has_post_thumbnail() and provide a fallback so your templates don’t break on posts without an image. Leave lazy-loading to WordPress unless the image is a hero, and once you have an attachment ID from anywhere, the wp_get_attachment_* functions work for featured and non-featured images alike.

Related: how to get a post ID, get the post title, get the current page slug, or browse the full WordPress code snippets library.