Footprint - Find what slows your site

Footprint is a performance profiler that tells a WordPress administrator which plugins and which theme have the highest impact on the performance of a given page — and what to do about it. A lighter site is also a more sober site, both for your visitors and for the planet. Unlike profilers built for developers (Query Monitor, Code Profiler), Footprint is decision-oriented. In thirty seconds you should know:

• which plugin or theme slows the page the most,
• which one ships the heaviest JS/CSS,
• which one issues the most SQL queries,
• which one consumes the most memory,
• which one calls external services,
• whether the active theme has a meaningful footprint of its own,
• what to optimise first.

When you re-scan the same URL, the report shows what changed since the previous scan: score, server time, memory, SQL, external calls — and the components whose impact moved most. How it works Footprint runs a differential scan: it loads the target URL once with everything active (baseline) and once per plugin with that plugin disabled — for the duration of a single internal HTTP request only. The difference between the two runs gives a real measurement of that plugin's footprint, not an estimation. A small must-use plugin loader performs the per-request swap. You install it in one click the first time you scan (it lives in wp-content/mu-plugins/, outside this plugin's folder, and is removed on uninstall). Nothing is changed in your database. The whole report you see on screen is computed locally on your server: the per-component impact on time, memory, SQL and assets, the ranking of the heaviest components, and the optimization advice. The plugin is fully functional on its own. The only thing that needs the Footprint Pulse service is the A-E Footprint Score, which compares your result against the anonymized measurements of thousands of other sites and cannot be computed locally. Honesty about limits Footprint provides estimated measurements where exact attribution is impossible. WordPress loads the core, plugins and theme inside the same PHP process, which makes perfect per-plugin memory attribution unreliable. The differential scan greatly improves the signal but it is still subject to:

• run-to-run variance (typically 5-15%),
• dependency cascades (disabling a parent plugin can disable extensions of it),
• page caches (a cached page bypasses PHP and yields no useful measurement),
• opcode and object cache warm-up effects.

The report flags any of these conditions when detected. Privacy Footprint includes a community ranking called Footprint Pulse. Sharing is on by default and can be turned off any time in Settings. The plugin's local report, per-component impact and recommendations work exactly the same either way. The only thing sharing adds is the community A-E Footprint Score described above. When sharing is enabled, after each scan the plugin sends to https://www.wpfootprint.com:

• the slug and version of each measured plugin and the active theme,
• time, memory and SQL counts attributed to each component (the same numbers shown on screen),
• the number of scripts, styles and external HTTP calls each component added,
• WordPress, PHP and MySQL versions,
• an anonymous site identifier generated locally on your server.

What is not sent: the URL of your pages, your content, visitor data, IP addresses, cookies, user accounts, database content, API keys, file paths, server hostnames. On first enrollment only, your domain is sent once so Pulse can call back into your WordPress AJAX endpoint to verify a cryptographic signature that proves you own the site. The domain is kept on the server for audit and re-verification, never displayed publicly, and never attached to your scans.

• No tracking, no advertising, no third-party SDK.
• The scan never modifies wp-config.php or your database content.
• Visitors are never profiled — only signed admin-initiated scans collect data.
• Turning sharing off stops the network call entirely; previously contributed measurements stay aggregated and anonymous.

Third-party services This plugin transmits data to Footprint Pulse (https://www.wpfootprint.com), a service operated by ByUs for the purpose described in the Privacy section above. As stated above, sharing is enabled by default and can be turned off at any time from the in-plugin Settings panel — disabling it stops the network call entirely.

• Service URL: https://www.wpfootprint.com
• Privacy policy: https://www.wpfootprint.com/privacy
• Terms of service: https://www.wpfootprint.com/terms

1. Upload the plugin to your /wp-content/plugins/ directory.
2. Activate Footprint through the Plugins menu in WordPress.
3. Go to Tools > Footprint and click Analyse the home page, or enter an internal URL to scan.

The first time you run a scan, Footprint asks you to install a small PHP file (a must-use plugin) into wp-content/mu-plugins/ (outside the plugin folder). The file is shipped with the plugin, is added only after you click to confirm, is required for the differential scan, and is automatically removed when Footprint is deactivated.

0.23.1

• Clearer consent before installing the must-use helper: the prompt now states explicitly that a PHP file is added to wp-content/mu-plugins/. The file is shipped with the plugin, installed only after the admin clicks to confirm, and removed on uninstall.

0.23.0

• The full report (per-component time, memory, SQL and asset impact, ranking and advice) is now computed and shown locally on your server, with or without community sharing. The community A-E Footprint Score is the only part that uses the Footprint Pulse service.
• The must-use measurement helper is no longer installed silently. The first scan asks for a one-time confirmation before writing it to wp-content/mu-plugins/.

0.22.12

• Renamed the "Time Δ" column to "Gain (ms)" with a help tooltip explaining that values are individual deltas and don't add up — clearer for non-technical users.

0.22.9

• Initial public release.