Meta
Title, description, canonical, robots and meta tags
Warnings Length, missing tags, canonical pointing to another URL, noindex
On-page SEO
An SEO inspector to check any page in one click
Smart Design Inspector’s SEO inspector shows the title, description, headings, structured data, hreflang, robots.txt, sitemap and llms.txt of any page, and warns you about what’s wrong.
The whole SEO inspector is free
SEO · yourclient.example
- MissingOpen GraphNo image when shared
- Needs workDescription182 characters
- Needs workHeadingsJump from H2 to H4
| Title | Web design for small businesses | Your Client | OK |
| Description | Fast, easy-to-edit websites for small businesses… | Needs work |
| Canonical | / | OK |
| Robots | index, follow | OK |
| OG image | — | Missing |
| hreflang | en · es · x-default | OK |
| llms.txt | /llms.txt | OK |
- H1Web design for small businesses
- H2Services
- H3Business websites
- H3Online stores
- H2Pricing
- H4Basic planH2 → H4 jump
- H2Contact
Your Clienthttps://yourclient.example › services
Web design for small businesses | Your Client
Fast, easy-to-edit websites for small businesses. Design, SEO and maintenance from a single team…
No image
yourclient.example
Web design for small businesses | Your Client
01
What it checks
10 blocksPreview
How the page looks in Google (desktop and mobile) and when shared on social media, X, LinkedIn and WhatsApp
Warnings Open Graph with no image or a cropped image
Headings
H1-H6 tree
Warnings No H1, more than one H1, skipped levels
Structured data
JSON-LD and microdata, in readable form
Warnings Syntax errors and empty required fields
Languages
The page’s hreflang
Warnings Missing return link or x-default
Domain files
robots.txt, sitemap.xml and llms.txt
Warnings Blocking search engines or AI crawlers
Images
Alt, file size, format and dimensions
Warnings No alt, empty alt and oversized images (more than 1.5 times their on-screen size)
Links
Internal, external, nofollow and sponsored, highlighted on the page
Core Web Vitals
Live LCP, CLS and INP, with the culprit element highlighted
Warnings Values outside Google’s thresholds
External audits
Opens the page in PageSpeed Insights, Google (site:), OpenGraph.xyz and isitagentready.com. With Pro, 10 more (WAVE, Schema, W3C, security, Wayback, Ahrefs)
02
What it has that others don’t
4 differencesllms.txt and AI crawlers
See whether the website lets AI bots in and whether it publishes an llms.txt. Hardly any SEO extension checks this. And in one click you can open it in isitagentready.com to see if it’s ready for AI agents.
Core Web Vitals with the culprit
Google retired its Web Vitals extension in January 2025. Here you see the value and the element causing it, highlighted on the page.
Compare with competitors
Every check is saved as a card and compared with other websites in a table.
Compare websites →In your language
The most popular SEO extensions are English-only. This one comes in 8 languages.
03
How to use it
3 steps- 01
Open the page you want to check.
- 02
Click the icon and choose SEO. Warnings appear at the top, sorted by severity.
- 03
If you want to compare it, save it as a card.
| Free€0forever | Pro€49one-time payment | |
|---|---|---|
| The whole SEO inspectorMeta, preview, headings, structured data, languages, domain files, images, links and Core Web Vitals | ||
| Open the page in external audits | 4: PageSpeed Insights, Google site:, OpenGraph.xyz and isitagentready.com | The 4 + 10: WAVE, rich results, Schema, W3C HTML and CSS, security (3), Wayback and AhrefsWith the first Pro release |
| Save the check as a card and compare it | 3 cards and 2 websites on screen | Unlimited cards and a table exportable to CSV or MarkdownFree early access |
05
What it doesn’t do
LimitsIt doesn’t give keyword volumes, domain authority or backlinks. That data comes from paid databases (Semrush, Ahrefs, Moz). The inspector sticks to what’s on the page and its domain, which is why it works without an account.
Is it free?
Yes. The whole SEO inspector is free forever. Pro adds the exportable comparison and design features.
Does it work with websites built with React or Next.js?
Yes. It reads the page as rendered in the browser. Seeing what Google gets in the server HTML is a feature planned for a later version.
Do I need an account or an API key?
No. Everything is calculated in your browser.
Does it validate structured data like Google does?
It checks the syntax and the most common required fields. For rich result eligibility, Google’s Rich Results Test is still the reference.
What is llms.txt?
A file at the root of a website that summarizes its content for AI models. The extension tells you whether it exists and shows it to you.
Does it measure real Core Web Vitals?
It measures the ones from your visit, live. Real-user data (CrUX) will come with Pro.
Which browsers and operating systems does it work on?
Chrome, Edge, Brave, Arc, Opera and Vivaldi, on Windows, Mac and Linux, from version 1.0. It works the same everywhere because the browser runs the extension, not the operating system. The code is ready to be brought to Firefox and Safari without a rewrite. While it’s in development, things may change.
Waitlist
Be one of the first to try it
Smart Design Inspector is in development. Leave your email and we’ll let you know the day it goes live on the Chrome Web Store, with the 3 Pro features free in early access.
One email on launch day and very few more · Unsubscribe in one click