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ncatlab.org

https://ncatlab.org· First analyzed 05 May 2026· Updated 05 May 2026
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ncatlab.org
Desktop screenshot of ncatlab.org
Mobile screenshot of ncatlab.org
Mobile

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Hosting Provider

Carnegie Mellon University

IP Address

128.2.25.48

Site Location

🇺🇸 United Statesvia ip

Server Location

🇺🇸 Pittsburgh, United States

ASN

AS9

Organization

Carnegie Mellon University

Server

Nginx

CDN

Cloudflare

WAF

Cloudflare

Nameservers

bailey.ns.cloudflare.com.quincy.ns.cloudflare.com.

Performance

79

Core Web Vitals

Weight

First Contentful Paint
2.4 s10%
Speed Index
3.1 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
738 KB
14 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
Carnegie Mellon University
CDN
Cloudflare

Technology Stack

2 Technologies Detected

Web Servers

1
Nginxv1.20.1

CDN

1
Cloudflare

SEO Analysis

D50/100
14
9
1
Meta Tags4/15
Content12/12
Headings6/8
Technical11/25
E-E-A-T0/7
Images0/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
N
ncatlab.orgncatlab.org

nLab

No description available for this page.

Title Length4 chars

Recommended: 50-60 chars (~24px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

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

10 issues found

Upgrade to view details

Crawlability

Sitemap
robots.txt

458 rules

Local SEO

Local Search Readiness

3/100
Poor
1 14 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

F39/100
Bot Access
20/25
Machine Read.
10/25
Schema Data
0/25
Citation
9/25

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
code blocks
Text ratio:24%
Words:1,980
Token eff.:Optimal
Sections/1K:5.6
Depth:1/5

Structured Data

No Schema

Citation Readiness

Opening Summary23w
Descriptive Headingsavg 3.7w
Canonical URL
Open Graph0/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (10)
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.
C
66/100
8
Passed
5
Critical
1
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
9/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
10/15
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
11/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
1/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
2 recommendations
  • •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.
63/100
A
75 mg
CO₂e / view
737.9 KB
Page Weight
80%
Cleaner Than
New Visitor
85 mg
vs
Returning (cached)
43 mg
Annual (10K/mo)
8.9 kg
Emission Segments
Data Center
4 mg
Network
22 mg
Device
49 mg
Resource Breakdown
JavaScript
292.6 KB
CSS
393.4 KB
HTML
51.9 KB
Green Hosting Verified
Cloudflare
GWF Verified
3 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
B

Security Score

76%Good
Interactive

HTTPS

No WAF

31d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

ECDSA (secp256r1) (256 bit)

Signature

ECDSA with SHA-384

TLS Version

TLSv1.3

HTTP Protocol

HTTP/1.1

Valid From

07.03.2026

Valid Until

05.06.2026

Subject Alternative Names (2)

ncatlab.orgnforum.ncatlab.org

SHA-256 Fingerprint

66:F9:7B:0B:BB:D4:35:85:DB:71:4B:30:6A:68:8B:45:9F:3D:EB:D9...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

cache-control
🟡 0s(private, max-age=0, must-revalidate)
connection
keep-alive
content-length
52879
content-security-policy
default-src 'self'; script-src 'self' 'unsafe-inline' 'unsaf...
content-type
application/xhtml+xml; charset=utf-8
date
Tue, 05 May 2026 17:00:08 GMT
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

100

SPF
DKIM
DMARC

DMARC Policy

Reject (Strictest)

MX Records (1)

saunders2.andrew.cmu.edu

Domain Information

ncatlab.org

Domain Age
17y 5m

Created

27.11.2008

Expires

27.11.2026

Last Updated

19.11.2025

Registrar

eNom, LLC

DNSSEC
Not Enabled

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
63/100
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
1 recommendation
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

DejaVu Serif

WCAG Partial
64/100
Readability
/30
22/30

18px · LH 1.30

Hierarchy
/20
12/20

2.5x ratio

WCAG
/25
17/25

3.54:1 min contrast

Performance
/25
13/25

1 font · 1 req

Heading Font

DejaVu Serif

Serif45px

Body Font

DejaVu Serif

Serif18px

Contrast Ratio

3.54:1

3 issues

Reading Comfort

~33 CPL

Narrow lines
45px
h1
29px
h2
16px
h3
18px
p

✅ Excellent readability: 18px body text is ideal for all devices.

⚠️ Tight line spacing (1.30). Increase to 1.4–1.6 for better readability.

⚠️ Partial contrast: 3 elements below WCAG AA threshold (min 3.5:1).

⚠️ Minor heading issue: 0 level skip(s) detected. Maintain sequential order for screen readers.

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

⚠️ Text justify detected: Justified text creates uneven word spacing, hurting readability on web.

Buy on MyFontsFlesch 53

Color Palette

6 unique colors
2.61:1 Fail Light
#ffffff
Background· 92.2%
#96a496
Other· 1.4%
#afbfaf
Primary· 1.9%
#c2d1c3
Border· 1.8%
#ebf6e2
Accent· 1.1%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

1
Google AnalyticsFree

User behavior and product analytics

1

Categories

1

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

12 Resources

7
Scripts
5
Styles
0
Async
0
Defer

Top Script Sources

local(7)

Website Identity

ncatlab.org

17 years old
Location detected: 🇺🇸 United Statesvia ip
eNom, LLC

Social Profiles

GitHub

Sponsored

Last analyzed: 05 May 2026 at 17:00

Historical Analysis & Change Tracking

ncatlab.org Technology Stack - Built With Nginx, Cloudflare | StackOptic | StackOptic