Pubchem.ncbi.nlm.nih.gov - SEO Checker

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Overview of the SEO Check
Meta information
54% 
Page quality
38% 
Page structure
58% 
Link structure
0% 
Server
70% 
External factors
100% 
SEO Score
Response time
1.02 s
File size
861.40 kB
Words
0
Media files
0
Number of links
0 internal / 0 external

Task list of SEO Improvements

Meta specifications

Title
(Critically important)
PubChem
The page title is too short. (91 pixels of 580 max pixel length) Optimize title
The page title is only one word.
There are no duplicate words in the title
Meta description
(Critically important)
Search and explore chemical information in the world's largest free chemistry database. Search chemicals by name, molecular formula, structure, and other identifiers. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more.
The meta description is too long: 1815 pixels from max. 1000 pixels. Optimize description
Crawlability
(Critically important)
There are no problems in accessing the website.
Canonical URL
(Important)
https://pubchem.ncbi.nlm.nih.gov/
There is a valid canonical link specified.
Language
(Somewhat important)
Language defined in HTML: en
Server location: United States of America
The following language is defined by HTML: en
Alternate/Hreflang Links
(Somewhat important)
There are no alternate links specified on this page.
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.
Domain
(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.
The character encoding is not specified in the HTTP header.
Doctype
(Nice to have)
The doctype HTML 5 is set correctly.
The doctype is placed at first in the HTML code.
Favicon
(Nice to have)
The favicon is linked correctly.

Meta tags

NameValue
robotsindex,follow,noarchive
application-namePubChem
msapplication-TileColor#0071bc
msapplication-config/pcfe/favicon/browserconfig.xml
theme-color#ffffff
viewportwidth=device-width, initial-scale=1
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ncbi_apppc-search
ncbi_pdidhome-search-interface
pubchem_tracking_categoryhome-search-app
google-site-verificationKrle6l-D_oS3d_gshIhpw3A34jPi0cLruyz88eiYljY
descriptionSearch and explore chemical information in the world's largest free chemistry database. Search chemicals by name, molecular formula, structure, and other identifiers. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more.
langen
og:titlePubChem
og:urlhttps://pubchem.ncbi.nlm.nih.gov/
og:imagehttps://pubchem.ncbi.nlm.nih.gov/pcfe/logo/PubChem_logo_splash.png
og:typewebsite
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og:descriptionPubChem is the world's largest collection of freely accessible chemical information. Search chemicals by name, molecular formula, structure, and other identifiers. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more.
charsetUTF-8

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Page quality

Content
(Critically important)
There are only 0 words on this page. Use at least 250 words to provide useful information.
No paragraphs were detected.
No placeholders texts or images were found.
Frames
(Critically important)
This page does not use a frameset.
Mobile optimization
(Somewhat important)
The file size of the HTML document is very large (861.4 kB).
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 6 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.
HTTPS
(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

No media files were found.

Page structure

H1 heading
(Critically important)
There is no H1 heading specified.
Headings
(Important)
There are no headings specified on the page. Headings are important for search engine optimization and help to structure your content.

Heading structure

No headings were found.
This page seems to be an entry page, because only very few links were found.
There are no external links on this page.

Found links on this page

No internal links were found.

Server configuration

HTTP redirects
(Critically important)
This page redirects to "https://pubchem.ncbi.nlm.nih.gov/"
HTTP header
(Important)
No X-Powered HTTP header is sent.
This page uses GZip for compressed data transmission.
Performance
(Somewhat important)
The page response time is slow (1.02 seconds). The response time should be less than 0.4 seconds. Slow websites are bad for search engine bots and also result in bad user experience.
The file size of the HTML document is very large (861 kB).

HTTP Response Header

NameValue
strict-transport-securitymax-age=31536000; includeSubDomains; preload
referrer-policyorigin-when-cross-origin
content-security-policyupgrade-insecure-requests
dateFri, 08 Nov 2024 00:29:00 GMT
serverApache
last-modifiedThu, 10 Oct 2024 19:28:20 GMT
accept-rangesbytes
cache-controlmax-age=86400
expiresSat, 09 Nov 2024 00:29:00 GMT
content-typetext/html
varyAccept-Encoding
content-encodinggzip
x-ua-compatibleIE=Edge
x-xss-protection1; mode=block
access-control-allow-origin*
statuscode200
http_versionHTTP/2

External factors

This page is referenced by wikipedia.
This website has excellent links from other websites.
This page has backlinks from 26,060 referring domains.
This page has 10,274,430 backlinks.
This page has backlinks from 16,630 different ip addresses.

Links from Wikipedia

You can find more links using Wikipedia search

Robots.txt

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Sitemap: https://pubchem.ncbi.nlm.nih.gov/sitemap/pcsitemap.xml
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Sitemap: https://pubchem.ncbi.nlm.nih.gov/sitemap/sitemap.cgi?p=taxonomy/sitemap_index.xml

# ==========================================================
# Version: 2004-10-01, PubChem Team
# Revision: 2005-2023

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pubchem.ncbi.nlm.nih.gov
PubChem
Search and explore chemical information in the world's largest free chemistry database. Search chemicals by name, molecular formula, structure, and other identifiers. Find chemical and physical properties, biological activities, safety and toxicity information, patents, literature citations and more.

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