Iupac.org - SEO Checker

Overview of the SEO Check
Meta information
100% 
Page quality
88% 
Page structure
79% 
Link structure
51% 
Server
69% 
External factors
100% 
SEO Score
Response time
0.89 s
File size
81.20 kB
Words
1174
Media files
20
Number of links
113 internal / 21 external

Task list of SEO Improvements

Meta specifications

Title
(Critically important)
International Union of Pure and Applied Chemistry
The length of the page title is perfect. (446 pixels out of 580 max pixel length)
There are no duplicate words in the title
Meta description
(Critically important)
IUPAC serves the international scientific endeavor in the dual function of a basic science and a mission-oriented Union. The Union is in a unique position
The length of the meta description is perfect. (935 pixels out of 1000 max pixel length)
Crawlability
(Critically important)
There are no problems in accessing the website.
Canonical URL
(Important)
https://iupac.org/
There is a valid canonical link specified.
Language
(Somewhat important)
Language detected in text: en
Language defined in HTML: en-us
Server location: Canada
The following language is defined by HTML: en-us
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)
The domain is no subdomain.
The domain length is good.
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 charset encoding (UTF-8) is set correctly.
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
viewportwidth=device-width, initial-scale=1
ajaxUrlhttps://iupac.org/wp-admin/admin-ajax.php
robotsindex, follow, max-image-preview:large, max-snippet:-1, max-video-preview:-1
descriptionIUPAC serves the international scientific endeavor in the dual function of a basic science and a mission-oriented Union. The Union is in a unique position
et-api-versionv1
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tec-api-versionv1
tec-api-originhttps://iupac.org
article:modified_time2025-04-04T14:15:40+00:00
langen-us
twitter:cardsummary_large_image
og:localeen_US
og:typewebsite
og:titleInternational Union of Pure and Applied Chemistry
og:descriptionIUPAC serves the international scientific endeavor in the dual function of a basic science and a mission-oriented Union. The Union is in a unique position
og:urlhttps://iupac.org/
og:site_nameIUPAC | International Union of Pure and Applied Chemistry
charsetUTF-8

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Page quality

Content
(Critically important)
This page contains 1174 words. That's ok.
31.9% of the text are stop words.
Keywords used in the page title are also used in the page content. That's good!
The page contains a listing, which indicates a good text layout.
16 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 21.93 words is good.
Frames
(Critically important)
This page does not use a frameset.
Mobile optimization
(Somewhat important)
No Apple touch icon is specified.
A viewport "width=device-width, initial-scale=1" is provided.
Bold and strong tags
(Somewhat important)
The usage of strong and bold tags is perfect. We recommend the use of up to 23 tags for this page.
Image SEO
(Somewhat important)
10 images have no alt attribute. The content of alt attributes is used by search engines.
Social Networks
(Nice to have)
This page is optimized perfectly for social networks.
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

URLAlt attributeTitle
...hemes/iupac/dist/images/logo.png?v=6.7.1IUPAC | International Union of Pure and Applied Chemistry
...ts.guidestar.org/gximage2?o=8474193&l=v4Guidestar Logo
.../iupac/dist/images/pt-challenge-logo.pngPeriodic Table Challenge
...mes/iupac/dist/images/gwb-logo-small.pngGlobal Women's Breakfast
...hemes/iupac/dist/images/iupac-top-10.pngTop 10
...mes/iupac/dist/images/iupac-100-logo.pngIUPAC 100
...es/iupac/dist/images/chemvoices-logo.pngChemVoices
.../themes/iupac/dist/images/icons/shop.svgVisit the IUPAC shop
...nvito-Tavola-PeriodicaIUPAC-1024x247.jpgNo alt attribute provided
...amanda-lawrence-3qiuE65ky0c-unsplash.jpgNo alt attribute provided
...oads/2024/01/j_cti-2023-0009_fig_002.jpgNo alt attribute provided
...nt/uploads/2023/02/Orange-book_2023.jpegNo alt attribute provided
...025/04/CI4702-Apr2025_cover-711x1024.pngNo alt attribute provided
...ntent/uploads/2024/08/hero-gwb-2025.webpNo alt attribute provided
/wp-content/uploads/2021/11/iupac.pngNo alt attribute provided
...7/laila-gebhard-Kl4BVIS9Lr4-unsplash.jpgNo alt attribute providedlaila-gebhard-Kl4BVIS9Lr4-unsplash
...ploads/2024/07/EPF2025_Martiniplaza.webpNo alt attribute providedEPF2025_Martiniplaza
...tent/uploads/2024/02/greenschool2024.pngNo alt attribute providedgreenschool2024
...themes/iupac/dist/images/footer-gfx.webpgraphic with iupac colors
...hemes/iupac/dist/images/logo.png?v=6.7.1IUPAC | International Union of Pure and Applied Chemistry

Page structure

H1 heading
(Critically important)
There is no H1 heading specified.
Headings
(Important)
The structure of headings is missing one or more levels. Do not skip heading levels.

Heading structure

Heading levelContent
H2 IUPAC 2025
H2 Sustainable Digital Standards
H2 in Chemistry International
H2 Top Ten Emerging Technologies in Chemistry
H2 Accelerating Equity in Science
H2 Diversity and Inclusion
H2 Featured Projects
H2 Have you seen CI lately?
H2 GWB
H2 Advancing the Worldwide Role of Chemistry
H2 Upcoming Events
H3 Sustainable Chemistry for Net Zero
H3 European Polymer Congress 2025 (EPF 2025)
H3 XVII Postgraduate Summer School on Green Chemistry
H4 Explore
H4 Contact
H4 The Periodic Table of Elements in Italian
H4 Terminology and Classification of Per- and Poly-Fluoroalkyl Substances (PFAS)
H4 InChI Open Education Resource (OER)
H4 Vocabulary of Concepts and Terms in Analytical Chemistry - the revised Orange Book (4th edition)
H5 Follow Us
Some anchor texts are used more than once.
5 links don't have an anchor text.
There are 1 links with a trivial 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 21 external links on this page.
LinkAttributesAnchor text
https://iupac.org/IMG-ALT IUPAC | International Union of Pure and Applied Chemistry
https://www.guidestar.org/prof...New window External Subdomain IMG-ALT Guidestar Logo
/periodic-table-challengeIMG-ALT Periodic Table Challenge
A-TITLE Periodic Table Challenge
https://iupac.org/gwb/2025IMG-ALT Global Women's Breakfast
A-TITLE Global Women's Breakfast
/what-we-do/top-ten/IMG-ALT Top 10
https://iupac.org/100IMG-ALT IUPAC 100
A-TITLE IUPAC 100
https://chemvoices.org/New window External IMG-ALT ChemVoices
A-TITLE ChemVoices
https://iupac.org/contactContact
https://iupac.org/my-profileProfile
https://iupac.org/my-profileLogin
/registration-optionsJoin
https://iypt2019.org/New window External IYPT 2019
A-TITLE IYPT 2019
https://iupac.org/shopNew window Shop
IMG-ALT Visit the IUPAC shop
https://iupac.org/who-we-are/Who We Are
/who-we-are/member-organizations/Member Directory
/who-we-are/organizational-chart/Organizational Chart
/who-we-are/strategic-plan/Strategic Plan
/who-we-are/divisions/Divisions
/who-we-are/committees/Committees
/who-we-are/organizational-gui...Governance
/who-we-are/our-leadership/Leadership
/who-we-are/secretariat/Secretariat
/who-we-are/our-history/History
https://iupac.org/what-we-do/What We Do
/what-we-do/periodic-table-of-...Periodic Table of Elements
/what-we-do/top-ten/Top 10 Emerging Technologies
/what-we-do/recommendations/Recommendations and Reports
/what-we-do/nomenclature/Nomenclature
/what-we-do/digital-standards/Digital Standards
/what-we-do/databases/Databases
/what-we-do/journals/Journals
/what-we-do/books/Color Books
/what-we-do/awards/Awards
/what-we-do/jcgm/JCGM
/what-we-do/projects/Projects
/what-we-do/conferences/Conferences
https://iupac.org/eventsEvents
https://iupac.org/projects/Text duplicate Projects
https://iupac.org/news/News
https://iupac.org/who-we-are/Text duplicate Who We Are
/who-we-are/member-organizations/Text duplicate Member Directory
/who-we-are/organizational-chart/Text duplicate Organizational Chart
/who-we-are/strategic-plan/Text duplicate Strategic Plan
/who-we-are/divisions/Text duplicate Divisions
/who-we-are/committees/Text duplicate Committees
/who-we-are/organizational-gui...Text duplicate Governance
/who-we-are/our-leadership/Text duplicate Leadership
/who-we-are/secretariat/Text duplicate Secretariat
/who-we-are/our-history/Text duplicate History
https://iupac.org/what-we-do/Text duplicate What We Do
/what-we-do/periodic-table-of-...Text duplicate Periodic Table of Elements
/what-we-do/top-ten/Text duplicate Top 10 Emerging Technologies
/what-we-do/recommendations/Text duplicate Recommendations and Reports
/what-we-do/nomenclature/Text duplicate Nomenclature
/what-we-do/digital-standards/Text duplicate Digital Standards
/what-we-do/databases/Text duplicate Databases
/what-we-do/journals/Text duplicate Journals
/what-we-do/books/Text duplicate Color Books
/what-we-do/awards/Text duplicate Awards
/what-we-do/jcgm/Text duplicate JCGM
/what-we-do/projects/Text duplicate Projects
/what-we-do/conferences/Text duplicate Conferences
https://iupac.org/eventsText duplicate Events
https://iupac.org/projects/Text duplicate Projects
https://iupac.org/news/Text duplicate News
/home/national-adhering-organi...National Adhering Organizations
/home/associated-organizations/Associated Organizations
/home/company-associates/Company Associates
/home/individual-members/Affiliate Program
/presidents-forum/Presidents’ Forum
https://www.facebook.com/IUPAC...New window External Subdomain A-TITLE Facebook
https://www.flickr.com/photos/...New window External Subdomain A-TITLE Flickr
https://www.instagram.com/iupa...New window External Subdomain A-TITLE Instagram
https://www.linkedin.com/compa...New window External Subdomain A-TITLE LinkedIn
https://twitter.com/IUPACNew window External A-TITLE Twitter
https://www.youtube.com/channe...New window External Subdomain A-TITLE YouTube
https://bsky.app/profile/iupac...New window External A-TITLE Bluesky
https://iupac.org/feed/New window A-TITLE RSS Feed
/event/53rd-iupac-general-asse...Follow the Congress and GA plan
/event/digital-data-standards-...LEARN MORE
/etoc-chemistry-international-...DIVE IN
/iupac-2024-top-ten-emerging-t...See All 2024 finalists
https://iupac.org/gwb/2025/Follow the day
/diversity-and-inclusion/Trivial anchor text
READ MORE
https://iupac.org/Anchor No Text
https://iupac.org/projectsSee All Projects
/project/2024-009-2-200No Text
/project/2024-006-3-100No Text
/project/2018-012-3-024No Text
/project/2012-005-1-500No Text
/what-we-do/journals/chemistry...Take A Flip
https://iupac.org/gwb/No Text
https://iupac.org/who-we-are/Learn More
https://iupac.org/eventsSee All Events
/event/sustainable-chemistry-f...International Conference
A-TITLE Sustainable Chemistry for Net Zero
/events/category/international...Text duplicate International Conference
/event/sustainable-chemistry-f...Sustainable Chemistry for Net Zero
A-TITLE Sustainable Chemistry for Net Zero
/event/european-polymer-congre...Text duplicate International Conference
A-TITLE European Polymer Congress 2025 (EPF 2025)
/events/category/international...Text duplicate International Conference
/event/european-polymer-congre...European Polymer Congress 2025 (EPF 2025)
A-TITLE European Polymer Congress 2025 (EPF 2025)
/event/xvii-postgraduate-summe...Summer School
A-TITLE XVII Postgraduate Summer School on Green Chemistry
/events/category/summer-school/Text duplicate Summer School
/event/xvii-postgraduate-summe...XVII Postgraduate Summer School on Green Chemistry
A-TITLE XVII Postgraduate Summer School on Green Chemistry
http://eepurl.com/hW6VDfNew window External Subscribe to Newsletter
https://iupac.org/Text duplicate IMG-ALT IUPAC | International Union of Pure and Applied Chemistry
/who-we-are/member-organizations/Text duplicate Member Directory
/who-we-are/our-leadership/Text duplicate Leadership
/who-we-are/strategic-plan/Text duplicate Strategic Plan
/who-we-are/divisions/Text duplicate Divisions
/who-we-are/committees/Text duplicate Committees
/who-we-are/organizational-gui...Text duplicate Governance
/what-we-do/periodic-table-of-...Text duplicate Periodic Table of Elements
/what-we-do/nomenclature/Text duplicate Nomenclature
/nomenclature-and-terminology/Terminology
/what-we-do/databases/Text duplicate Databases
/what-we-do/journals/Text duplicate Journals
/what-we-do/recommendations/Recommendations & Reports
/what-we-do/top-ten/Top Ten Emerging Technologies
/what-we-do/digital-standards/Text duplicate Digital Standards
/what-we-do/books/color-books/Text duplicate Color Books
https://iupac.org/projects/Text duplicate Projects
/what-we-do/conferences/Text duplicate Conferences
/what-we-do/awards/Text duplicate Awards
https://www.facebook.com/IUPAC...New window External Subdomain Text duplicate A-TITLE Facebook
https://www.flickr.com/photos/...New window External Subdomain Text duplicate A-TITLE Flickr
https://www.instagram.com/iupa...New window External Subdomain Text duplicate A-TITLE Instagram
https://www.linkedin.com/compa...New window External Subdomain Text duplicate A-TITLE LinkedIn
https://twitter.com/IUPACNew window External Text duplicate A-TITLE Twitter
https://www.youtube.com/channe...New window External Subdomain Text duplicate A-TITLE YouTube
https://bsky.app/profile/iupac...New window External Text duplicate A-TITLE Bluesky
https://iupac.org/feed/New window Text duplicate A-TITLE RSS Feed
https://www.theedigital.com/we...New window External Subdomain WordPress Development
A-TITLE WordPress Website Development
https://www.theedigital.com/we...New window External Subdomain Custom Programming
A-TITLE Custom Programming
https://www.theedigital.com/New window External Subdomain TheeDigital
A-TITLE Raleigh Web Design Agency

Server configuration

HTTP redirects
(Critically important)
This page redirects to "https://iupac.org/"
HTTP header
(Important)
The X-powered header is sent within the response header. (unnecessary)
The web server transmits the web page (HTML) in compressed form.
Performance
(Somewhat important)
The page response time of 0.89 seconds is longer than the recommended limit of 0.4 seconds. A high response time unnecessarily slows down search engine crawling and results in bad user experience as well.
The file size of the HTML document is fine (81 kB).

HTTP Response Header

NameValue
dateSat, 31 May 2025 10:32:00 GMT
content-typetext/html; charset=UTF-8
varyAccept-Encoding
x-pingbackhttps://iupac.org/xmlrpc.php
link<https://iupac.org/wp-json/>; rel="https://api.w.org/"
x-et-api-versionv1
x-et-api-roothttps://iupac.org/wp-json/tribe/tickets/v1/
x-et-api-originhttps://iupac.org
x-tec-api-versionv1
x-tec-api-roothttps://iupac.org/wp-json/tribe/events/v1/
x-tec-api-originhttps://iupac.org
x-powered-byWP Engine
x-cacheableSHORT
cache-controlmax-age=600, must-revalidate
x-cacheHIT: 26
x-cache-groupnormal
cf-cache-statusDYNAMIC
set-cookie275 Characters
servercloudflare
cf-ray9485ce09d8e19eb1-CDG
content-encodingbr
alt-svch3=":443"; ma=86400
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 1,613 referring domains.
This page has 38,996 backlinks.
This page has backlinks from 836 different ip addresses.

Robots.txt

Crawl-delay: 10
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User-agent: *
Disallow:

Sitemap: https://iupac.org/sitemap_index.xml
Sitemap: https://iupac.org/100/sitemap_index.xml
Sitemap: https://iupac.org/shop/sitemap_index.xml
Sitemap: https://iypt2019.org/sitemap_index.xml
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Search preview

iupac.org
International Union of Pure and Applied Chemistry
IUPAC serves the international scientific endeavor in the dual function of a basic science and a mission-oriented Union. The Union is in a unique position

Most important keywords

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

KeywordResultRecheck
IUPAC70%Check
International63%Check
International Union61%Check
Chemistry International60%Check
Union59%Check
IUPAC serves58%Check
Chemistry55%Check
Applied Chemistry53%Check
mission-oriented Union53%Check
international scientific endeavor51%Check

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