How do I create a custom error page in WordPress?

Creating a Custom 404 Error Page in WordPress

Basic Method: Using Theme Files

The simplest way to create a custom 404 page is by adding or modifying the 404.php file in your theme:

1. Create a 404.php file in your theme directory
2. Add your custom content
3. Style it to match your site's design

Basic 404.php template example:

<?php get_header(); ?>

<div class="error-page">
    <h2>Oops! Page Not Found</h2>
    <p>We couldn't find the page you were looking for.</p>
    
    <div class="search-form">
        <?php get_search_form(); ?>
    </div>
    
    <div class="helpful-links">
        <h3>You might want to try:</h3>
        <ul>
            <li><a href="<?php echo home_url(); ?>">Home Page</a></li>
            <li><?php wp_nav_menu(array('theme_location' => 'primary')); ?></li>
        </ul>
    </div>
</div>

<?php get_footer(); ?>

Advanced Method: Using Templates

Create a custom template for more control:

1. Create a new page in WordPress
2. Create a custom template file
3. Assign the template to your 404 page

Custom template file example:

<?php
/*
Template Name: Custom 404
*/

get_header();

// Get recent posts
$recent_posts = wp_get_recent_posts(array(
    'numberposts' => 4,
    'post_status' => 'publish'
));
?>

<div class="custom-404">
    <h2>Page Not Found</h2>
    
    <div class="suggested-content">
        <h3>Latest Posts</h3>
        <ul>
            <?php
            foreach($recent_posts as $post) {
                echo '<li><a href="' . get_permalink($post['ID']) . '">' . $post['post_title'] . '</a></li>';
            }
            ?>
        </ul>
    </div>
</div>

<?php get_footer(); ?>

Redirect Method Using .htaccess

Custom error page redirect using .htaccess:

ErrorDocument 404 /404-custom-page/

Best Practices

1. Keep it simple and clear
2. Include a search box
3. Add navigation options
4. Show related/popular content
5. Maintain brand consistency
6. Add analytics tracking
7. Keep load time fast

SEO Considerations

1. Use proper HTTP status code (404)
2. Include relevant internal links
3. Add structured data if needed
4. Monitor 404 errors in Google Search Console

Security Tips

1. Don't reveal system information
2. Validate all user inputs
3. Sanitize output
4. Use WordPress security functions

Recommended Plugins

1. 404page (WordPress.org)

   • Easy custom 404 page creation
   • No coding required
   • Multiple template options

2. All 404 Redirect to Homepage (WordPress.org)

   • Simple redirect solution
   • Log 404 errors
   • Custom redirect options

Common Pitfalls to Avoid

1. Don't redirect all 404s to homepage
2. Avoid automatic redirects without user consent
3. Don't overload the page with too much content
4. Keep error messages user-friendly
5. Don't forget mobile responsiveness

Analytics Integration

Add 404 page tracking code:

<?php
// Add to your 404.php or custom template
if (function_exists('ga_tracking_code')) {
    ga_tracking_code('404_error', 'Page not found: ' . $_SERVER['REQUEST_URI']);
}
?>

Remember to test your 404 page regularly and update content as needed. Monitor your error logs to identify and fix broken links proactively.