Forge12 Interactive GmbH

F12 Profiler analyzes your WordPress site comprehensively and delivers concrete, prioritized recommendations to improve load times. The plugin combines server diagnostics, asset analysis, database optimization, and plugin impact assessment in a modern, clean interface.
<h4>Features</h4>
Analysis & Diagnostics
<ul>
<li>Server analysis (PHP, MySQL, OPcache, web server, SSL, HTTP/2, compression)</li>
<li>Automatic site crawler with load time measurement (desktop & mobile)</li>
<li>Asset analysis (CSS, JS, images) with optimization potential</li>
<li>OPcache status & configuration recommendations</li>
<li>PHP profiler (runtime, queries, hooks, plugin ranking, culprit analysis)</li>
<li>Plugin impact analysis (assets, hooks, queries per plugin)</li>
<li>PageSpeed Insights integration (Lighthouse Scores + Core Web Vitals + CrUX)</li>
<li>Performance score with 6 weighted categories (A-F grades, trend delta)</li>
<li>Recommendation engine with automatic optimization suggestions</li>
</ul>
Optimization Tools
<ul>
<li>Lazy Loading (images and iframes)</li>
<li>Font Display Optimization (font-display: swap/optional/fallback/block)</li>
<li>Script Defer Manager (automatic defer for scripts with exclusion list)</li>
<li>Auto Image Dimensions (prevents Layout Shifts / CLS)</li>
<li>HTML Minification (whitespace, comments, empty attributes)</li>
<li>CSS/JS Minification (file-based cache)</li>
<li>WordPress Bloat Removal (emojis, embeds, Dashicons, jQuery Migrate, XML-RPC, Heartbeat, and more)</li>
<li>Browser Cache (.htaccess-based)</li>
<li>DNS Prefetch & Preconnect (domain detection from asset scan)</li>
<li>Database Analysis (8 categories with detail view)</li>
<li>Autoload Manager (granular wp_options management)</li>
<li>Background Asset Scanner with conflict detection</li>
<li>File-based Page Cache with TTL and URL exclusion (Pro)</li>
<li>CSS/JS Asset Manager – disable, defer, async per page or globally (Pro)</li>
<li>Conditional Loading – shortcode, block, regex, archive, login status, post type, plugin (Pro)</li>
<li>Smart auto-suggestions with source-based plugin detection after full scan (Pro)</li>
<li>Asset Preload Manager – Link headers for critical assets (Pro)</li>
<li>Critical CSS Generator & Applier – above-the-fold CSS per template (Pro)</li>
<li>Unused CSS Removal – per page template, safelist, regex safelist (Pro)</li>
<li>WebP Image Conversion with batch queue and backup (Pro)</li>
<li>LQIP Image Placeholders – 20px blur-up previews with IntersectionObserver (Pro)</li>
<li>Preload Key Requests – LCP images, fonts, critical resources (Pro)</li>
<li>Script Delay – delays third-party JS until first user interaction (Pro)</li>
<li>Local Google Fonts – GDPR-compliant WOFF2 self-hosting (Pro)</li>
<li>YouTube/Vimeo Facade – thumbnail + play button instead of iframe (Pro)</li>
<li>Database Cleanup – one-click per category or bulk action (Pro)</li>
<li>Redis Object Cache Management – drop-in installation/removal (Pro)</li>
<li>Scheduled Crawls & Cleanups via WP-Cron (Pro)</li>
<li>Performance Budgets with email/webhook notifications (Pro)</li>
<li>Settings Import/Export as JSON (Pro)</li>
<li>One-Click Optimizer – automated optimization with backup & restore (Pro)</li>
<li>License Management with activation/deactivation (Pro)</li>
</ul>
User Interface
<ul>
<li>Modern iOS-style design system</li>
<li>React 18 + TypeScript SPA</li>
<li>30+ pages/tools with dedicated configuration</li>
<li>Context-sensitive info sections on all pages</li>
<li>Pro features visible with lock icon and upgrade prompt</li>
</ul>
<a href="https://www.forge12.com/f12-profiler-pro/" rel="nofollow ugc">Get F12 Profiler Pro</a>
<h4>System Requirements</h4>
<ul>
<li>WordPress 6.0 or higher</li>
<li>PHP 8.0 or higher</li>
<li>MySQL 5.7 / MariaDB 10.3 or higher</li>
</ul>

F12 Profiler

Excellent! After P3 doesn’t work with PHP7+ anymore, F12 seems finally the one stepping in to fill that gap.

Update [18-Jun-19]. After some small contributions of mine to the dev efforts, the plugin developer has decided to add me to the team, long after this review was written.

Finally an alternative to P3

Comprehensive WordPress performance analysis with crawling, load time measurement, server diagnostics, and integrated optimization tools. Free.

Eugen Bobrowski

This is tool that help developers and administrators easier getting information.
The debug bar is available on front side for everyone if WP_DEBUG is true. If you are admin you can open bar on any page. Hover the mouse cursor to bottom right corner and click on
<h4>Features:</h4>
<ul>
<li>Implementation time counter</li>
<li>Queries counter</li>
<li>Queries list (sortable)</li>
<li>Memory counter</li>
<li>Segment checker</li>
<li>Cron jobs information</li>
<li>WP_Cache counter</li>
<li>phpinfo() window</li>
<li>References menu</li>
<li>Image Puller that provide pull missed images from production to develop site</li>
</ul>
Implementation time counter
It count the time from plugin loaded action to debug bar. 
It does not consider processes that implement before and during the plugins are loading.
Queries counter
It count all what is queried via $wpdb object.
Queries list
It show all what is queried via $wpdb object.
The <code>SAVEQUERIES</code> constant must be defined as <code>true</code>.
Memory counter
Returns the amount of memory, in bytes, that’s currently being allocated to your PHP script.
Segment checker
Also you can check any segment of your code.
<pre><code>do_action('check_segment', 'segment_1');

//do somethisng

do_action('check_segment', 'segment_1');
</code></pre>
The code below returns in debug bar new item like this:
<blockquote>
segment_1: 14.14/3/1
</blockquote>
The digits there ara time, queries and how many times this code was implemented.
References menu
The default one item of this menu is Errors. It shows notices and warnings including case when <code>WP_DEBUG</code> is false.
And also you can easy add your item to this menu and print there any var_dump or anything else.
<pre><code>add_filter('wp_debug_refs', 'my_debug_tool_ref');

function my_debug_tool_ref ($refs) {

 global $post;

 $refs['my_ref_id'] = array(
 'title' => 'My ref',
 'content' => 'My ref' . var_export($post, true),
 );
 return $refs;
}
</code></pre>

Debug Tool

Show helpful debug bar at front and admin side. Tool for developers.

F12 Profiler vs Debug Tool