You turned on a speed plugin. Now your menu won't open, your checkout looks broken, or your fonts are gone — and you have no idea which setting did it.
Cache and optimization plugins make sites faster by combining and minifying files, deferring and delaying JavaScript, removing "unused" CSS, and lazy-loading images. When it works, it's great. When it breaks something, it breaks
silently — and the settings that caused it are buried across dozens of checkboxes. Even the plugins' own "safe mode" just turns whole categories off and leaves you to bisect the rest by hand.
Speed Autopsy is the post-mortem. It finds what your optimizer broke,
names the setting responsible, and tells you how to fix it — without touching a single setting itself.
What it does
- Detects your active cache/optimization plugins (LiteSpeed Cache, WP Rocket, Autoptimize, W3 Total Cache, SiteGround Optimizer, WP-Optimize, Perfmatters, FlyingPress, WP Fastest Cache) and reads — never changes — their current settings.
- Confirms real breakage. It fetches your own pages and checks whether the combined and minified files your optimizer generates actually load. A combined stylesheet or script that is missing or empty is the single most common catastrophic failure — your page requests a file that isn't there, so its styles or scripts silently vanish. Speed Autopsy catches exactly this.
- Names the risky setting. It cross-references the settings you have enabled against a knowledge base of known-breakage patterns — Remove Unused CSS breaking dropdowns and cart drawers, Combine JavaScript killing sliders and menus, Delay JavaScript stopping the checkout, lazy-load hiding slider images — and tells you the symptom to look for and the exact setting to change.
- Gives you a clear verdict: confirmed breakage, risky settings enabled, or all clear.
Strictly read-only, by design
Speed Autopsy
never changes a setting, deactivates a plugin, clears a cache, or modifies your site in any way. It reads and it fetches — that's all. Every fix it suggests is for
you to apply, in control, when you're ready. A diagnostic you can trust must never be a hand on the controls.
Also included, free
- Scan the pages you choose — the front page always, plus your shop, cart and key landing pages (the ones where breakage actually costs money)
- Weekly automatic scan + an email when new issues appear
- Findings report with severity, plain-language symptom and fix, and dismiss-with-note
- Site Health integration
- WP-CLI:
wp speed-autopsy scan / status, including --format=json
- A REST status endpoint (
spau/v1/status, administrators only) with the verdict and open findings as JSON, for your own dashboards and tooling
- An honest loopback self-check: if your host blocks self-requests, Speed Autopsy says "scan impaired" — it never pretends everything is fine
Speed Autopsy Pro
Pro adds the runtime layer a server-side scan can't see, plus agency tools: an
opt-in, admin-only JavaScript-error collector that catches the actual errors and failed asset loads hit in the browser while testing — correlated to the deferred or combined script that caused them —
Slack and webhook alerts when a scan finds new breakage, and a
white-label client report (print / save as PDF). Sold and licensed through Freemius (see "External services").
This is a diagnostic, not a fixer
Speed Autopsy does not speed up your site, does not change your optimizer, and cannot guarantee a fix — it tells you, in plain language, what your optimizer appears to have broken and what to change. You stay in control of every change.