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nlm.gov

https://nlm.gov· First analyzed 24 May 2026· Updated 24 May 2026
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nlm.gov
Desktop screenshot of nlm.gov
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Mobile

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Hosting Provider

National Library of Medicine

IP Address

130.14.16.110

Site Location

🇺🇸 United Statesvia ip

Server Location

🇺🇸 Washington, United States

ASN

AS70

Organization

National Library of Medicine

Server

AmazonS3

CDN

CloudFront

Nameservers

ns3.nih.gov.lhcns1.nlm.nih.gov.lhcns2.nlm.nih.gov.ns2.nih.gov.+1 more

Performance

99

Core Web Vitals

Weight

First Contentful Paint
810 ms10%
Speed Index
1.1 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
1.2 MB
77 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Platform
AWS CloudFront
CDN
CloudFront

Technology Stack

7 Technologies Detected

Analytics

3
Google Analytics
Google Analytics 4
Crazy Egg

CSS Frameworks

1
Tailwind CSS

Icon Libraries

1
Font Awesome

Fonts

1
Google Fonts

Tag Managers

1
Google Tag Manager

SEO Analysis

C65/100
18
7
1
Meta Tags10/15
Content12/12
Headings8/8
Technical14/25
E-E-A-T0/7
Images4/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
N
nlm.govnlm.gov

National Library of Medicine - National Institutes of Health

No description available for this page.

Title Length60 chars

Recommended: 50-60 chars (~352px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing meta description — important for click-through rates in SERPs

8 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

25,530 URLs

robots.txt

32 rules

Local SEO

Local Search Readiness

13/100
Poor
4 11 2

This site doesn't appear to be a local business. Local SEO signals are optional for non-local websites.

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AI & LLM Readiness

D41/100
Bot Access
20/25
Machine Read.
14/25
Schema Data
0/25
Citation
7/25

AI Bot Access

14/14 accessible
AI Search
OAI-SearchBot
PerplexityBot
Claude-SearchBot
Gemini-Deep-Research
DuckAssistBot
Training
GPTBot
ClaudeBot
Google-Extended
Meta-ExternalAgent
Bytespiderinfo
Amazonbot
Applebot-Extended
CCBotinfo
Fetch
ChatGPT-User

Machine Readability

llms.txt
llms-full.txt
Semantic HTML
Heading Hierarchy
navheader/footer
Text ratio:13%
Words:637
Token eff.:Optimal
Sections/1K:22
Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary17w
Descriptive Headingsavg 3.8w
Canonical URL
Open Graph0/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (9)
AI readiness recommendation preview...
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Accessibility

WCAG 2.1 Compliance

Evaluates how accessible your website is for users with disabilities, based on WCAG 2.1 guidelines. Checks images, forms, keyboard navigation, ARIA roles, and color contrast.
A
88/100
15
Passed
0
Critical
1
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
20/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
15/15
Verifies form fields have labels, error messages are clear, and inputs are properly associated.
Color & Contrast
15/15
Tests text-to-background color contrast ratios against WCAG AA/AAA minimum requirements.
Keyboard & Focus
13/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
5/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
1 recommendation
  • •Accessibility recommendation preview...
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Carbon Footprint

SWDM v4 · Eco-Score

Carbon emissions estimated using the Sustainable Web Design Model v4 (SWDM v4). Factors in data center, network, and device energy across new and returning visitors. Grade thresholds based on HTTP Archive percentiles.
37/100
C
149 mg
CO₂e / view
1.2 MB
Page Weight
70%
Cleaner Than
New Visitor
170 mg
vs
Returning (cached)
85 mg
Annual (10K/mo)
17.8 kg
Emission Segments
Data Center
33 mg
Network
36 mg
Device
80 mg
Resource Breakdown
JavaScript
169.6 KB
Images
755.6 KB
CSS
258.1 KB
Fonts
2.1 KB
HTML
7.9 KB
Other
7.8 KB
Green Hosting Not Verified
National Library of Medicine
5 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
D

Security Score

51%Poor
Interactive

HTTPS

WAF

284d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Amazon

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

04.02.2026

Valid Until

04.03.2027

OCSP Stapling

Enabled

Subject Alternative Names (9)

*.nlm.nih.govnlm.govwww.nlm.netnlm.netmainweb.awsprod.nlm.nih.govwww.nlm.orgnlm.orgwww.nlm.gov+1 more

SHA-256 Fingerprint

B6:62:7C:2A:2B:53:53:06:2B:DA:11:F0:C1:8B:B8:64:F7:CC:94:BF...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

age
614
content-encoding
📦 Gzip(gzip)
content-type
text/html
date
Sun, 24 May 2026 11:36:03 GMT
etag
W/"2f3f63fb157105980f75e01e617d683f"
last-modified
Thu, 16 Apr 2026 16:13:36 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

70

SPF
DKIM
DMARC

DMARC Policy

Reject (Strictest)

MX Records (3)

nihcesxway4.hub.nih.gov
nihcesxway3.hub.nih.gov
nihcesxway5.hub.nih.gov

Domain Information

nlm.gov

Domain Age
27y 12m

Created

03.06.1998

Expires

28.07.2026

Last Updated

20.10.2025

Registrar

get.gov

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

Mobile Compatibility

Viewport & Responsive Test

Tests how well your website works on mobile devices. Checks viewport configuration, responsive layout, touch targets, font readability, and simulates rendering across different screen sizes.
C
68/100
Mobile Friendly1 breakpoint
Viewport Meta
The viewport meta tag tells mobile browsers how to scale the page. Without it, mobile devices render at desktop width.
Responsive Design
Uses CSS media queries or flexible layouts to adapt content to different screen sizes automatically.
Touch Icons
Apple touch icons and favicons displayed when users add the site to their home screen on mobile devices.
Readable Font Size
Base font size should be at least 16px on mobile to ensure text is readable without zooming.
Relative Units
Using em, rem, %, or vw instead of fixed px values allows content to scale properly across screen sizes.
No H-Scroll Risk
No elements wider than the viewport that would cause horizontal scrolling on mobile devices.
Tap Targets OK
Interactive elements (buttons, links) are at least 48x48px with enough spacing to prevent accidental taps.
No Fixed Widths
No elements with fixed pixel widths that could overflow on smaller screens and break the layout.
Viewport
width=device-width, initial-scale=1, shrink-to-fit=no
1 recommendation
  • •Mobile compatibility recommendation preview...
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Typography & Readability

Roboto

WCAG AA
72/100
Readability
/30
22/30

16px · LH 1.50

Hierarchy
/20
14/20

2.5x ratio

WCAG
/25
18/25

4.61:1 min contrast

Performance
/25
18/25

1 font · 4 req

Heading Font

Roboto

Sans40px

Body Font

Roboto

Sans16px

Contrast Ratio

4.61:1

WCAG AA (≥4.5:1)

Reading Comfort

~34 CPL

Narrow lines
40px
h1
33px
h2
28px
h3
16px
p

✅ Excellent readability: 16px body text is ideal for all devices.

✅ Optimal line spacing: 1.50 ratio (ideal range 1.4–1.6).

❌ Very complex text: Flesch score 6/100. Consider shorter sentences and simpler words.

✅ WCAG AA contrast: All text meets 4.5:1 ratio (min 4.6:1).

❌ Missing H1: Every page should have exactly one H1 element for SEO and accessibility.

✅ Strong hierarchy: Headlines are 2.5x larger than body text.

GGoogle FontsFlesch 6

Color Palette

8 unique colors
Light
#ffffff
Background· 36.900000000000006%
#edf2f6
Background· 15.7%
#326195
Primary· 14.000000000000002%
#0b1e26
Primary· 10.9%
#2d4b56
Secondary· 7.4%
#d1dbe1
Secondary· 6.1%
#42647b
Secondary· 4.8%
#7c939c
Secondary· 4.3%

Business & Marketing Stack

3 Tools Detected

Growing

Behavior Analytics

3
Google Tag ManagerFree
Google AnalyticsFree
Crazy EggSMB

User behavior and product analytics

1

Categories

3

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

25 Resources

20
Scripts
5
Styles
7
Async
0
Defer

Top Script Sources

googletagmanager.com(5)siteintercept.qualtrics.com(4)local(3)script.crazyegg.com(2)assets.nlm.nih.gov(2)

Website Identity

nlm.gov

27 years old
Location detected: 🇺🇸 United Statesvia ip
get.goven

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Last analyzed: 24 May 2026 at 11:45

Historical Analysis & Change Tracking