- SEO Checker

Overview of the SEO Check
Meta information
Page quality
Page structure
Link structure
External factors
SEO Score
Response time
0.32 s
File size
41.70 kB
Media files
Number of links
59 internal / 34 external

Task list of SEO Improvements

Meta specifications

(Critically important)
MDN Web Docs
The page title is too short. (146 pixels of 580 max pixel length) Optimize title
There are no duplicate words in the title
Meta description
(Critically important)
The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
The length of the meta description is perfect. (961 pixels out of 1000 max pixel length)
(Critically important)
There are no problems in accessing the website.
Canonical URL
There is a valid canonical link specified.
(Somewhat important)
Language detected in text: en
Language defined in HTML: en-us
Server location: United States of America
The following language is defined by HTML: en-us
Alternate/Hreflang Links
(Somewhat important)
The alternate link to the page itself is missing.
Other meta tags
(Somewhat important)
There is no rel next meta tag on this page.
There is no rel prev meta tag on this page.
(Somewhat important)
This page is hosted on a subdomain. Use a top level domain for better SEO results.
The domain does not contain non-latin characters.
Page URL
(Somewhat important)
No parameters were found in the URL.
No session ID was found in the URL.
The URL does not have too many subdirectories.
Charset encoding
(Somewhat important)
The character encoding is not specified in the HTTP header.
The charset encoding (UTF-8) is set correctly.
(Nice to have)
The doctype HTML 5 is set correctly.
The doctype is placed at first in the HTML code.
(Nice to have)
The favicon is linked correctly.

Meta tags

descriptionThe MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
og:titleMDN Web Docs
og:descriptionThe MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.
og:image:altThe MDN Web Docs logo, featuring a blue accent color, displayed on a solid black background.
og:site_nameMDN Web Docs

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Page quality

(Critically important)
These Typos were found:
  • improvments => improvements
This page contains 546 words. That's ok.
22.9% of the text are stop words.
Keywords used in the page title are also used in the page content. That's good!
Words from the H1 heading are used in the page content.
The page contains a listing, which indicates a good text layout.
6 paragraphs were found on this page.
The text content is perfect.
No placeholders texts or images were found.
There are no duplicates on the site.
The average number of words per sentence of 14.33 words is good.
(Critically important)
This page does not use a frameset.
Mobile optimization
(Somewhat important)
A viewport "width=device-width,initial-scale=1" is provided.
At least one Apple touch icon is specified.
Bold and strong tags
(Somewhat important)
The usage of strong and bold tags is perfect. We recommend the use of up to 11 tags for this page.
Image SEO
(Somewhat important)
Alt text (alternative text) is correctly used on all found images.
Social Networks
(Nice to have)
There are only a few social sharing widgets on the page. Make your website popular in social networks with social sharing widgets.
Additional markup
(Nice to have)
No additional page markup was found.
(Somewhat important)
This website uses HTTPS to protect privacy and integrity of the exchanged data.
All included files are also transferred via HTTPS.

Media list

URLAlt attributeTitle
/assets/mdn_contributor.pngTiled Mozilla Logo

Page structure

H1 heading
(Critically important)
Resources for Developers, by Developers
The H1 heading is perfect.
The heading structure is perfect.

Heading structure

Heading levelContent
H1 Resources for Developers, by Developers
H2 Featured articles
H2 Latest news
H2 Recent contributions
H2 Support
H2 Our communities
H2 Developers
H3 Developer essentials: JavaScript console methods
H3 Introduction to web sustainability
H3 CSS Custom Highlight API
H3 <color>
H3 Contributor Spotlight
Some anchor texts are used more than once.
1 links don't have an anchor text.
The number of internal links is ok.
None of the anchor texts is too long.
All internal links are not using dynamic parameters.
There are too many external links (34) on this page.
LinkAttributesAnchor text Skip to main content Skip to search Text
/es/docs/WebOverview / Web Technology Web technology reference for developers
/es/docs/Web/HTMLHTML Structure of content on the web
/es/docs/Web/CSSCSS Code used to describe document style
/es/docs/Web/JavaScriptJavaScript General-purpose scripting language
/es/docs/Web/HTTPHTTP Protocol for transmitting web resources
/es/docs/Web/APIWeb APIs Interfaces for building web applications
/es/docs/Mozilla/Add-ons/WebEx...Web Extensions Developing extensions for web browsers
/es/docs/WebWeb Technology Web technology reference for developers
/es/docs/LearnOverview / MDN Learning Area Learn web development
/es/docs/LearnMDN Learning Area Learn web development
/es/docs/Learn/HTMLHTML Learn to structure web content with HTML
/es/docs/Learn/CSSCSS Learn to style content using CSS
/es/docs/Learn/JavaScriptJavaScript Learn to run scripts in the browser
/es/docs/Web/AccessibilityAccessibility Learn to make the web accessible to all
/es/plusOverview A customized MDN experience
/es/plus/ai-helpAI Help (beta) Get real-time assistance and support
/es/plus/updatesUpdates All browser compatibility updates at a glance
/en-US/plus/docs/features/over...Documentation Learn how to use MDN Plus
/en-US/plus/docs/faqFAQ Frequently asked questions about MDN Plus
/en-US/plus/ai-helpAI Help Beta
/users/fxa/login/authenticate/...Nofollow Log in
/users/fxa/login/authenticate/...Nofollow Sign up for free
/en-US/blog/Text duplicate Blog
/en-US/blog/learn-javascript-c...Developer essentials: JavaScript console methods
/en-US/blog/Text duplicate Blog
/en-US/blog/introduction-to-we...Introduction to web sustainability
/en-US/docs/Web/APIWeb APIs
/en-US/docs/Web/API/CSS_Custom...CSS Custom Highlight API
/en-US/blog/mdn-curriculum-lau...Lift-off: The MDN Curriculum launch
/en-US/blog/baseline-evolution...Baseline's evolution on MDN
/en-US/blog/Text duplicate
/en-US/blog/introducing-the-md...Introducing the MDN Playground: Bring your code to life!
/en-US/blog/Text duplicate Fix CHIPS typo mdn/content Add link to preconnect Text duplicate mdn/content minor improvments to 'information for web authors' Text duplicate mdn/content Refer from <select> to HTMLSelectElement.value Text duplicate mdn/content [ko] sync translated content mdn/translated-content Remove JS select implementation Text duplicate mdn/content zh-CN: update Glossary/Fetch_directive Text duplicate mdn/translated-content zh-cn: update translation Glossary/Information_architecture Text duplicate mdn/translated-content [zh-cn]: update the translation of `webrtc-data-channels` Text duplicate mdn/translated-content zh-cn: update translation Glossary/Fallback_Alignment Text duplicate mdn/translated-content
/en-US/communityGet involved → Text window External MDN on Mastodon window External MDN on X (formerly Twitter) window External MDN on GitHub
/en-US/blog/rss.xmlNew window MDN Blog RSS Feed
/en-US/blog/Text duplicate Blog window External Subdomain Careers
/en-US/advertisingAdvertise with us Subdomain Product help
/es/docs/MDN/Community/IssuesReport an issue
/en-US/communityMDN Community window External Subdomain MDN Forum
/discordNew window MDN Chat
/es/docs/WebWeb Technologies
/es/docs/LearnLearn Web Development
/es/plusMDN Plus window External Subdomain Hacks Blog window External Subdomain No Text window External Subdomain Website Privacy Notice window External Subdomain Anchor Cookies window External Subdomain Legal window External Subdomain Community Participation Guidelines window External Subdomain Mozilla Corporation’s window External Subdomain Mozilla Foundation
/es/docs/MDN/Writing_guideline...a Creative Commons license

Server configuration

HTTP redirects
(Critically important)
This page redirects to ""
HTTP header
No X-Powered HTTP header is sent.
This page uses GZip for compressed data transmission.
(Somewhat important)
The page response time is excellent with 0.32 seconds.
The file size of the HTML document is fine (42 kB).

HTTP Response Header

x-goog-hashcrc32c=CQ9gfA==, md5=hSzigCA3SxW2QAoxjhvJSw==
expiresSat, 01 Jun 2024 07:51:55 GMT
cache-controlpublic, max-age=3600
last-modifiedSat, 01 Jun 2024 00:46:59 GMT
alt-svch3=":443"; ma=2592000
content-security-policydefault-src 'self'; script-src 'report-sample' 'self' 'sha256-uogddBLIKmJa413dyT0iPejBg3VFcO+4x6B+vw3jng0=' 'sha256-EehWlTYp7Bqy57gDeQttaWKp0ukTTEUKGP44h8GVeik='; script-src-elem 'report-sample' 'self' 'sha256-uogddBLIKmJa413dyT0iPejBg3VFcO+4x6B+vw3jng0=' 'sha256-EehWlTYp7Bqy57gDeQttaWKp0ukTTEUKGP44h8GVeik='; style-src 'report-sample' 'self' 'unsafe-inline'; object-src 'none'; base-uri 'self'; connect-src 'self' https://* https://* https://*; font-src 'self'; frame-src 'self' * *; img-src 'self' * * * https://* https://*; manifest-src 'self'; media-src 'self'; child-src 'self'; worker-src 'self';
dateSat, 01 Jun 2024 06:51:55 GMT
serverGoogle Frontend
via1.1 google

External factors

(Nice to have)
This website is not classified "for adult only".
This page is referenced by wikipedia.
This website has excellent links from other websites.
This page has backlinks from 104 referring domains.
This page has 233 backlinks.
This page has backlinks from 89 different ip addresses.
Facebook popularity
(Somewhat important)
The page has 14041 shares and comments on Facebook.

Search preview
MDN Web Docs
The MDN Web Docs site provides information about Open Web technologies including HTML, CSS, and APIs for both Web sites and progressive web apps.

Most important keywords

Following keywords were found. You can check the keyword optimization of this page for each keyword.

MDN Web62%Check
MDN Web Docs61%Check
Web Resources56%Check
Web Technologies54%Check
Web APIs54%Check

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