The Anti-BS
Technical SEO Extension
I am done with SEO tools that charge $99/month to run a Lighthouse report and stick a logo on it. I am done with agencies that sell "proprietary audits" built entirely on free APIs. I am done with extensions that harvest your browsing data yet still miss half the actual problems on your page.
So I built this. A professional-grade technical SEO auditor that runs entirely in your browser. No accounts. No servers. No subscriptions. No privacy trade-offs. It just tells you what is wrong and gets out of your way.
It is 100% free. Always.
What I Built It To Do
Four core principles, zero compromises.
Instant Page Score
Open the extension and get a 0–100 health score broken down across Technical, Content, Performance, and Social dimensions. You see exactly what failed and why — no fluff, no "contact us for details."
100% Offline. Zero Tracking.
Every audit runs locally inside your browser tab. No backend server, no analytics pipeline, no login screen. The URLs you audit never leave your machine.
Run History
The Run History tab saves your past audits locally so you can track exactly how a score changes after you make edits. The most basic thing in the world that most tools gatekeep behind a paid plan.
See What Googlebot Actually Sees
I surface the rendered DOM, the raw HTML, and the diff between them. If your JavaScript is bloating your initial HTML by 300%, I flag it. Googlebot does not execute JS the way your browser does. This matters.
Every Single Thing It Audits
Not cherry-picked highlights. Not locked behind a tier. Every single one of these is included, free, right now.
TL;DR — Skip the essay, here's what it actually does
- Meta & Indexing: Title/Description/URL truncation, robots, canonicals, & stealthy X-Robots-Tags.
- Technical Basics: Viewport, language tags, and favicons.
- Content & Media: H1–H6 hierarchy, image alt text, lazy-loading flags, & CLS risks.
- Links & Schema: Internal/external link counts, rel flags (nofollow/ugc), & JSON-LD validation.
- JS & Performance: HTML DOM-diffing for hydration bloat, plus Core Web Vitals (LCP, CLS, INP).
- Quality & Social: Word counts, keyword density, readability scores, & Open Graph/Twitter validation.
- Advanced: Hreflang, sitemap/robots.txt verification, analytics tracker detection, & local NAP extraction.
Title, Description & URL
I extract the exact title tag and meta description and track their byte-accurate character length. Title truncation kicks in around 60 characters and 580 pixel-width. Description truncation hits at 155–160 chars. I tell you exactly where you stand. I also flag messy, parameter-heavy URLs that confuse crawlers and look terrible in SERPs.
Robots, Canonical & X-Robots-Tag
I check the standard robots and googlebot meta directives in the DOM. I also intercept HTTP response
headers to surface the X-Robots-Tag — the
invisible server-level directive that can silently noindex
your entire site without leaving a single trace in the
page source. Most SEO tools completely miss this.
Viewport, Language & Favicon
Missing viewport meta tag means Google's
mobile-first indexer may penalize you. Missing lang attribute means screen readers will guess and accessibility
audits will fail. A missing favicon makes your result
look untrustworthy in SERPs. I flag all three.
Heading Hierarchy (H1–H6)
I render your full heading tree with each tag's exact text, character length, and XPath location. One page must have exactly one H1. Skipping levels (H2 straight to H4) signals broken document logic. I make it immediately obvious where your hierarchy breaks down.
Image Audit
I separate images by alt text status. For each image
I capture the src, dimensions, and whether it is
lazy-loaded. Missing width/height attributes cause CLS layout jitter. Improperly lazy-loading
your hero image cripples LCP. And I filter out 1×1 tracking
pixels so they do not pollute your audit counts.
Link Diagnostics
I surface the total link count, split by internal
vs. external, and track unique links. I also flag
every link marked nofollow, sponsored, or ugc — the three rel qualifiers that
stop PageRank from flowing. If you are leaking authority
on paid advertising links without rel="sponsored", I will catch it.
JSON-LD Schema Validation
I extract every structured data block on the page and display it with full syntax highlighting. Rich Snippets — star ratings, FAQs, recipes, events — are only accessible through valid JSON-LD. I show you exactly what is there and make it easy to spot errors that block rich results.
DOM Diff (HTML Bloat Detection)
I capture the raw server-side HTML byte length, then the final rendered DOM byte length after JavaScript executes. If those numbers are wildly different, your page is client-side rendered — and Googlebot may never index your content. This is the single most important check for React, Angular, or Next.js sites, and almost no free tool surfaces it.
Core Web Vitals (LCP, CLS, INP)
I query live performance APIs to pull real Largest Contentful Paint (target: <2.5s), Cumulative Layout Shift (target: <0.1), and Interaction to Next Paint (target: <200ms) scores. These are direct Google ranking signals. I show you the raw numbers, not watered-down letter grades.
Content Analysis & Readability
I strip out all navigation, header, and footer chrome to measure the pure body text word count. I calculate keyword density and flag over-optimized pages that risk a Google quality penalty. I also score readability — high-performing consumer content typically targets an 8th-grade reading level to minimize bounce rate.
Open Graph & Twitter Cards
I verify your og:title, og:description, og:image, and Twitter Card tags.
Without these, every link you share on LinkedIn,
Discord, iMessage, or Slack renders as a plain-text
URL. I show you exactly what is missing so shared
links don't look like spam.
Hreflang & International SEO
If you run multi-region or multi-language sites, incorrect hreflang implementation means each regional variant fights against the other for the same rankings. I extract every hreflang pair — language code and target href — so you can immediately spot mismatches and missing reciprocal annotations.
Sitemap & Robots.txt
I check whether your robots.txt exists,
parse its crawl rules, and extract any sitemap URLs it
references. I then validate those sitemap URLs — confirming
existence, indexing scale (URL count), and last modification
date. A malformed robots.txt can block entire subdirectories
without you noticing for months.
Analytics & Tracking Detection
I scan the DOM payload to determine whether Google Analytics 4, Universal Analytics, or Google Tag Manager are present and surface their tracking IDs. Running blind without analytics is a critical, basic failure. I make sure you don't.
SERP Preview
A pixel-accurate simulation of how your page looks in Google search results on both Mobile and Desktop. If your title or description is going to get cut off at the SERP pixel boundary, I show you exactly where. Stop guessing.
A lightweight alternative to bloated toolbars.
Searching for a free alternative to Ahrefs SEO Toolbar, MozBar, or Detailed SEO? Most toolbars require a paid account just to see technical data. SEO Unmasked gives you professional-grade technical SEO metrics in one click, with zero subscription needed.
You don't need an SEO guru to fix the basics.
High rankings come down to fundamentals: non-misleading titles, a clear structure, fast load times, and content that answers the query.
While good agencies provide strategy, too many simply automate free tools and charge you for the summary. They profit from the mystery.
I built this to remove the mystery. This tool scans your page for the same technical flags those expensive reports look for. Find out what's broken, fix it yourself, and keep your money. It's 100% free — no catch, no upgrade. Just the raw truth.