What the SEO check looks at
The checker downloads the page the way a search engine first sees it, as the server sends it, and reads the HTML. It reports the HTTP status, response time, page size and redirects, then the title, meta description, H1, canonical URL, language, word count, images, links and any structured data it finds.
Every problem is listed with its severity. Errors usually block or seriously hurt indexing, such as a 4xx or 5xx status or a missing title. Warnings hurt how the page ranks or looks in results, such as a duplicate H1 or a very long title. Notices are smaller improvements, such as images without alt text.
The check reads the raw HTML and does not run JavaScript. If your site builds its content in the browser, what you see here is close to what crawlers get before rendering, which is useful for finding content that only appears after scripts run.
How to run an SEO check
- Paste the full URL of the page, starting with https://.
- Start the check and wait a few seconds while the page is fetched.
- Read the summary: status, response time, size and the number of issues.
- Go through the issues from errors to notices and fix them in your CMS or code.
- Run the check again to confirm the fixes.
Common findings and how to fix them
Missing or duplicate H1
Use exactly one H1 per page that says what the page is about. Theme templates often turn the logo or the product name into a second H1.
Canonical pointing elsewhere
A canonical tag that points to another URL tells Google to index that URL instead. Check it on paginated, filtered and tagged pages, where wrong canonicals are common.
Images without alt text
Alt text describes the image to screen readers and search engines. Describe what the image shows in a few words, for example "red trail running shoe, side view".
Frequently asked questions
Is this SEO checker free?
Yes, with no account. To keep it fast for everyone there is a limit on the number of checks per minute from the same address.
Can it check my whole website?
This tool checks one URL at a time. A Symbiote account runs full site audits that crawl every page, group the issues and track them over time.
Why does the checker say my page has no content?
Your page probably builds its content with JavaScript. The checker reads the HTML sent by the server, as crawlers do on the first pass. Server-side rendering or pre-rendering makes the content visible without scripts.
Can I check pages that require a login?
No. The checker only reads public pages, and it refuses private network addresses for security. Search engines cannot see pages behind a login either.
Does fixing these issues guarantee better rankings?
No tool can guarantee rankings. Fixing technical and on-page issues removes obstacles, so search engines can index and understand the page. Rankings also depend on content quality, relevance and links.
Related free tools
SERP preview
See how your page shows up in Google and check title and description length.
robots.txt checker
Check whether a URL can be crawled by search engines and list the sitemaps declared in robots.txt.
Schema markup generator (JSON-LD)
Generate structured data for products, articles, local businesses and FAQs.