Checks the page you're viewing for on-page SEO and AI readiness, inside your browser. Sends nothing anywhere.
Users
3
store count
Rating
5.0 / 5
unchanged in 30 days
Ratings
1
total ratings
Store rank
#290K
#239K among extensions
Version
0.1.0
updated 5 Oct 2026
About Narsil SEO Checker
Check the page you're on for on-page SEO and AI readiness, in one click, inside your browser. Narsil SEO Checker sends nothing anywhere.
It runs the same checks as the free Page Audit at narsilcreative.com/page-audit/, on pages that tool's server can't reach: staging sites, localhost, pages behind a login, and sites that block unknown bots.
WHAT IT CHECKS
A score out of 100 and 16 checks, each marked pass, warn, fail or info, with the reason in plain English. Where a check needs work and Narsil has a guide for it, the check links to the guide.
Metadata
• Title tag: present, and no longer than about 60 characters
• Meta description: present, and no longer than 160 characters
• Meta robots: whether the page tells search engines not to index it
• Canonical URL: whether the page names one
• Social sharing tags: og:title and og:image
Content
• H1: exactly one
• Section headings: whether the page has H2s
• Word count: under 150 words of visible text gets a warning
• Visible date: a published or updated date on the page
• Image alt text: images without it
AI readiness
• Answer-first opening: whether the first paragraph over 60 characters runs 80 to 500 characters. It measures length. Whether that paragraph answers the reader is yours to judge.
• Structured data: whether the page carries JSON-LD, and which types
• Question coverage: a heading with a question mark, or FAQ structured data
Links
• Internal links: fewer than 3 gets a warning
• External links: counted
• Anchor text: generic anchors like "click here"
THE FIVE PLACEMENTS
Type a target keyword and it checks the five places it belongs: the title tag, the meta description, the URL slug, the H1 and the first sentence. It matches whole words, so "art" doesn't count inside "start", and a plural is a different word. Chinese, Japanese, Korean and Thai keywords match inside longer text, since those languages don't separate words with spaces the same way. It also counts the keyword in the body and the headings.
WHAT IT READS, AND WHAT IT KEEPS
When you open it, it reads the page in that tab: the HTML as your browser shows it, web components included, the address, the content type and the HTTP status. It leaves out what's typed into the page's form fields, passwords included. Text typed into an editor on the page is part of the page, so it's read with the rest. The first time, it asks before it reads anything. The checks run inside your browser, with no server, no analytics and no account.
It keeps two things: that you agreed, and the keyword you typed for a tab, until you close the browser. Privacy policy: https://narsilcreative.com/seo-checker/privacy
It checks the page as your browser shows it, content built by JavaScript included. Known cookie banners, admin bars and chat widgets are set aside first, so their text doesn't count as the page's. Content inside web components (shadow DOM) is read too, except in a component built closed, which the page's own scripts can't read either.
WHO SHOULDN'T INSTALL IT
Anyone who needs a crawler, rank tracking, search volume or backlink data. It checks one page at a time and does none of those. For a whole site, Narsil SEO audits up to 250 pages a month and writes the fix for most of what it finds, from $12/month.
Made by Narsil Creative (narsilcreative.com). Not affiliated with Google.