RANKNIBBLER

Free On-Page SEO Checker

RankNibbler analyses any webpage and checks the key on-page SEO factors that affect how search engines index and rank your site. Enter a URL above and hit Analyse to get started.

How to Use RankNibbler

1. Enter a URL — paste any webpage address into the input box above and click Analyse.
2. Wait for the audit — RankNibbler fetches the page and runs over 30 on-page SEO checks in seconds.
3. Review your score — you will get a score out of 100 along with a detailed breakdown of what passed and what needs fixing.
4. Explore the tabs — dig into Meta Tags, Headings, Images, Links, Structured Data, Social/OG, Scripts, and more.
5. Fix the issues — use the recommendations provided to improve your on-page SEO and re-run the audit to track progress.
6. Download a PDF report — click Download PDF to get a full branded report you can share with clients or colleagues.

Standalone SEO Tools

In addition to the main audit, RankNibbler offers three standalone tools that you can use independently:

• SEO Compare — enter two URLs and an optional target keyword to see a side-by-side comparison of every on-page SEO factor. Find out which page is better optimised and where the gaps are. Ideal for competitor analysis and A/B testing.
• SERP Snippet Generator — preview exactly how your page will appear in Google search results. Fetch a live URL or type your own title and description to test variations. Includes pixel-width meters so you know exactly where Google will truncate your text.
• Redirect Checker — enter any domain to check whether all four URL variants (HTTP, HTTPS, WWW, non-WWW) redirect correctly to a single canonical URL. Detects redirect chains, temporary redirects, and missing redirects that cause duplicate content.
• Site Audit — enter a domain and RankNibbler crawls your sitemap.xml, discovers every page, and audits up to 30 pages automatically. Get a bird's-eye view of your entire website's SEO health with average scores, issue counts, and CSV export.
• Bulk URL Checker — paste up to 20 URLs and get SEO scores for all of them at once. Perfect for auditing a section of your site, comparing landing pages, or checking a list of competitor pages. Export results as CSV.
• Broken Link Checker — scan any page for dead links, 404 errors, and redirect chains. Checks up to 100 links per page and reports the HTTP status code for each one. Filter by broken links or redirects and export as CSV.

How the SEO Score Works

RankNibbler scores each page out of 100 based on the checks above. Points are awarded for each passing check and deducted for issues found.

Score Breakdown by Category

Why On-Page SEO Matters

On-page SEO is the foundation of search engine optimisation. While backlinks and domain authority play a role in rankings, search engines need to understand what your page is about before they can rank it. Proper title tags, meta descriptions, heading structure and structured data make it easier for Google and other search engines to crawl, index and rank your content. On-page issues are also the easiest to fix since you have full control over your own website.

On-Page SEO vs Off-Page SEO

On-page SEO covers everything within your control on the page itself: title tags, meta descriptions, headings, content quality, internal links, structured data, and technical elements like canonical tags and robots directives. Off-page SEO refers to external factors such as backlinks from other websites, social media signals, and domain authority. Both are important, but on-page SEO is where every website should start because you have complete control over it and the improvements take effect as soon as search engines recrawl the page.

Who Is RankNibbler For?

• Website owners — quickly check if your pages follow SEO best practices without needing technical knowledge.
• SEO professionals — audit client pages in seconds and share clear, actionable reports.
• Content writers — verify that your articles have the right meta tags, headings, and structure before publishing.
• Web developers — catch missing alt text, render-blocking scripts, and broken structured data during development.
• Marketing teams — ensure landing pages are properly optimised before running campaigns.

Frequently Asked Questions

Is RankNibbler free to use?

Yes, RankNibbler is completely free. There are no sign-ups, no limits, and no premium tiers. Enter any URL and get a full on-page SEO audit instantly.

What does RankNibbler check?

RankNibbler checks over 30 on-page SEO factors including title tags, meta descriptions, heading structure, image alt text, internal and external links, structured data, Open Graph tags, script loading, canonical URLs, robots directives, word count, text-to-HTML ratio, favicon, HTTPS, URL structure, keyword density, readability score, lazy loading, image dimensions, empty links, nofollow ratio, deprecated HTML, doctype, charset, tech stack detection, accessibility checks, social media links, RSS feeds, and CSS/JS file counts.

Does RankNibbler store the pages it analyses?

No. RankNibbler fetches the page in real time, runs the analysis in your browser, and does not store any page content. Your data stays in your browser session and is cleared when you close the tab.

How often should I run an SEO audit?

Run an audit whenever you publish or update a page. For existing pages, a monthly check is a good habit to catch any regressions or new issues. If you have made significant site changes such as a redesign, migration, or CMS update, audit your key pages immediately after.

Why is my score low even though my site looks fine?

A visually polished website can still have poor on-page SEO. Common hidden issues include missing meta descriptions, duplicate title tags, missing alt text on images, no structured data, and render-blocking scripts. These are invisible to visitors but affect how search engines understand and rank your pages.

Can RankNibbler check pages behind a login?

No. RankNibbler can only analyse publicly accessible pages. It fetches the page the same way a search engine bot would, so if the page requires authentication it cannot be audited.

What is a good SEO score?

A score of 80 or above is considered good and means the page follows most SEO best practices. A score of 50-79 means there are several issues worth fixing. Below 50 indicates significant problems that are likely hurting your search rankings. See the full score breakdown for details on how each check contributes to the total.

How do I fix a missing meta description?

Add a <meta name="description" content="Your description here"> tag inside the <head> section of your HTML. The description should be 120-160 characters, include your target keyword, and give searchers a reason to click. Most CMS platforms like WordPress have SEO plugins that make this easy. Learn more about meta descriptions.

What is keyword density?

Keyword density is the percentage of times a word appears on a page relative to the total word count. For example, if "shoes" appears 15 times in a 1,000-word article, the keyword density is 1.5%. RankNibbler's keyword density checker extracts the top keywords and phrases from any page so you can see what terms dominate your content.

What is structured data and do I need it?

Structured data is code (usually JSON-LD) that tells search engines exactly what your content is about — whether it is a product, article, FAQ, recipe, or business. It enables rich results in Google such as star ratings, FAQ dropdowns, and product prices. While not required, pages with structured data often get more clicks from search results. Use the structured data checker to see what your page has.

How do I check my website's SEO?

Enter your URL in the box at the top of this page and click Analyse. RankNibbler will fetch your page and run over 30 checks covering meta tags, headings, images, links, structured data, readability, keyword density, tech stack, accessibility, and more. You will receive a score out of 100 with clear recommendations for every issue found. It takes seconds and is completely free.

What technologies can RankNibbler detect?

RankNibbler identifies over 40 technologies from the HTML source code, including CMS platforms (WordPress, Shopify, Squarespace, Wix), JavaScript frameworks (React, Next.js, Vue.js, Angular), analytics tools (Google Analytics, Hotjar, Clarity), CDNs (Cloudflare, CloudFront), SEO plugins (Yoast, Rank Math), and more. See the full list on the tech stack checker page.

Free SEO Tools

Every check in RankNibbler is available for free with no sign-up required. Use these tools to analyse any publicly accessible webpage:

SEO Guides & Resources

Learn SEO from scratch or deepen your knowledge with our free guides:

How RankNibbler Compares

Most SEO audit tools require sign-ups, limit free usage, or charge monthly fees. RankNibbler is different. It runs entirely in your browser with no account required, checks over 30 on-page factors in seconds, and includes features that many paid tools do not offer — such as keyword density analysis, readability scoring, technology detection, and accessibility checks. Your page content is never stored on our servers. The audit happens in real time and the results stay in your browser session.

Last updated: March 2026