All Web Images Videos News
Settings
Appearance
Site Icons
Font Size
Font
General
Infinite Scroll
Open Links in a New Tab
Safe Search
Search Engine Optimization Overview
83
100
PNAS
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans the biological, physical, and social sciences.
https://www.pnas.org/action/cookieAbsent
1 high issue
3.0%
4 medium issues
12.1%
5 low issues
15.2%
23 tests passed
69.7%
0.31 seconds
11.88 kB
16 resources
Secure
Seo
Title
The title tag is perfect.
PNAS
Meta description
The meta description tag is good.
Proceedings of the National Academy of Sciences (PNAS), a peer reviewed journal of the National Academy of Sciences (NAS) - an authoritative source of high-impact, original research that broadly spans the biological, physical, and social sciences.
Headings
The headings are properly set.
  1. Request Username
  2. Create a new account
  3. Login
  4. Change Password
  1. Sign up for thePNAS Highlights newsletter
  1. Featured Topics
  2. Articles By Topic
  3. Featured Topics
  4. Articles By Topic
  5. Featured Topic
  6. Articles By Topic
  1. Congrats!
Content keywords
The content has relevant keywords.
pnas
Image keywords
All images have alt attributes set.
SEO friendly URL
The URL is SEO friendly.
https://www.pnas.org/action/cookieAbsent
404 page
The website has 404 error pages.
https://www.pnas.org/404-0a43e9cd13bc27e0f13dd3a0912a00cc
Robots.txt
The webpage can be accessed by search engines.
Noindex
The webpage has a noindex tag set.
In-page links
The number of links on the webpage is okay.
  1. https://www.pnas.org/
  2. https://www.pnas.org/
  3. Current Issue
  4. Latest Articles
  5. Special Features
  6. List of Issues
  7. Front Matter
  8. Information for Authors
  9. Editorial and Journal Policies
  10. Submission Procedures
  11. Publication Charges
  12. Physics
  13. Chemistry
  14. Sustainability Science
  15. Applied Mathematics
  16. Applied Physical Sciences
  17. Astronomy
  18. Biophysics and Computational Biology
  19. Computer Sciences
  20. Earth, Atmospheric, and Planetary Sciences
  21. Engineering
  22. Environmental Sciences
  23. Mathematics
  24. Statistics
  25. Anthropology
  26. Sustainability Science
  27. Demography
  28. Economic Sciences
  29. Environmental Sciences
  30. Political Sciences
  31. Psychological and Cognitive Sciences
  32. Anthropology
  33. Sustainability Science
  34. Agricultural Sciences
  35. Applied Biological Sciences
  36. Biochemistry
  37. Biophysics and Computational Biology
  38. Cell Biology
  39. Developmental Biology
  40. Ecology
  41. Environmental Sciences
  42. Evolution
  43. Genetics
  44. Immunology and Inflammation
  45. Medical Sciences
  46. Microbiology
  47. Neuroscience
  48. Pharmacology
  49. Physiology
  50. Plant Biology
  51. Population Biology
  52. Psychological and Cognitive Sciences
  53. Systems Biology
  54. 0 Cart
  55. Sign in
  56. Register
  57. Individual Login
  58. Institutional Login
  59. Advanced Search
  60. Covid-19
  61. Demography
  62. Monkeypox
  63. Climate Change
  64. Gun Violence
  65. https://www.pnas.org/
  66. https://www.pnas.org/action/showPreferences?menuTab=Alerts
  67. https://www.pnas.org/about/rss
  68. https://www.pnas.org/
  69. https://www.pnas.org/action/showPreferences?menuTab=Alerts
  70. https://www.pnas.org/about/rss
  71. Current Issue
  72. Special Features
  73. Colloquia
  74. List of Issues
  75. Collected Papers
  76. Front Matter
  77. Journal Club
  78. Podcasts
  79. About
  80. Diversity and Inclusion
  81. Authors
  82. Reviewers
  83. Subscribers
  84. Librarians
  85. Press
  86. Cozzarelli Prize
  87. PNAS Updates
  88. Contact
  89. Site Map
  90. Terms & Privacy Policy
  91. Accessibility
  92. Find out more
  93. CONTINUE
  94. Returning user
  95. here
  96. here
  97. Institutional Login
Language
The webpage has the language declared.
en
Favicon
The webpage does not have a favicon.
Performance
Text compression
The HTML file is compressed.
Load time
The webpage loaded in 0.31 seconds.
Page size
The size of the HTML webpage is 11,875.00.
HTTP requests
There are fewer than 16 HTTP requests on the webpage.
  1. https://static.cloudflareinsights.com/beacon.min.js/v652eace1692a40cfa3763df669d7439c1639079717194
  2. https://static.cloudflareinsights.com/beacon.min.js/v652eace1692a40cfa3763df669d7439c1639079717194
  3. https://www.pnas.org/products/pnas/releasedAssets/js/build.lazyload.bundle-022be1119580d9b29e90.js
  4. https://www.pnas.org/products/pnas/releasedAssets/js/main.bundle-58a0217b1ba0c158d095.js
  5. https://www.pnas.org/wro/lpsx~article-metrics-phase2.js
  6. https://static.cloudflareinsights.com/beacon.min.js/v652eace1692a40cfa3763df669d7439c1639079717194
  1. https://www.pnas.org/wro/lpsx~article-metrics-phase2.css
  2. https://www.pnas.org/products/pnas/releasedAssets/css/build-ff767f42b2434023e696.css
  3. https://www.pnas.org/products/pnas/releasedAssets/css/print-ff767f42b2434023e696.css
  4. https://www.pnas.org/pb-assets/styles/pnas-styles-1660679696617.css
  5. https://use.fontawesome.com/releases/v5.12.1/css/all.css
  1. https://www.pnas.org/pb-assets/images/Logos/header-logo/logo-1624644560537.svg
  2. https://www.pnas.org/pb-assets/images/Logos/header-logo/logo-light-1641218818190.svg
  3. https://www.pnas.org/pb-assets/images/Logos/header-logo/logo-1624644560537.svg
  4. https://www.pnas.org/pb-assets/images/Logos/footer/logo-footer-1624408444100.svg
  1. https://www.googletagmanager.com/ns.html?id=GTM-KCV32QR
Image format
There are 1 images that are not using the AVIF, WebP format.
  1. https://www.pnas.org/pb-assets/images/Logos/footer/logo-footer-1624408444100.svg
JavaScript defer
The are 3 javascript resources without the defer attribute.
  1. https://www.pnas.org/products/pnas/releasedAssets/js/build.lazyload.bundle-022be1119580d9b29e90.js
  2. https://www.pnas.org/products/pnas/releasedAssets/js/main.bundle-58a0217b1ba0c158d095.js
  3. https://www.pnas.org/wro/lpsx~article-metrics-phase2.js
DOM size
The DOM size is optimal.
The HTML file has 596 DOM nodes.
Security
HTTPS encryption
The webpage uses HTTPS encryption.
The HTML file has https://www.pnas.org/action/cookieAbsent DOM nodes.
Mixed content
There are no mixed content resources on the webpage.
Server signature
The webpage has a public server signature.
cloudflare
Unsafe cross-origin links
The webpage has 5 unsafe cross-origin links.
Plaintext email
The webpage contains plaintext emails.
  1. name@example.com
Miscellaneous
Structured data
The webpage has structured data.
    Meta viewport
    The webpage has a meta viewport tag set.
    width=device-width, initial-scale=1.0
    Character set
    The webpage has a charset value set.
    UTF-8
    Sitemap
    The website has sitemaps.
    1. https://www.pnas.org/sitemap-index-1.xml
    Social
    The webpage has 7 social links.
    Content length
    The are less than 500 words on the webpage.
    The webpage has 487 words.
    Text to HTML ratio
    The text to HTML ratio is under 10%
    The text to HTML ratio is 7%.
    Inline CSS
    The webpage contains inline CSS code.
    1. display:none;visibility:hidden
    2. display:none;
    Deprecated HTML
    There are no deprecated HTML tags on the webpage.