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opendefinition.org

https://opendefinition.org· First analyzed 28 Apr 2026· Updated 28 Apr 2026
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opendefinition.org
Desktop screenshot of opendefinition.org
Mobile screenshot of opendefinition.org
Mobile

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Hosting Provider

Cloudflare
cloudflare.com

IP Address

104.21.70.185

Site Location

🇨🇦 Canadavia ip

Server Location

🇨🇦 Toronto, Canada

ASN

AS13335

Organization

Cloudflare, Inc.

Server

Cloudflare

CDN

Cloudflare

WAF

Cloudflare

Nameservers

dana.ns.cloudflare.com.carl.ns.cloudflare.com.

Performance

100

Core Web Vitals

Weight

First Contentful Paint
587 ms10%
Speed Index
763 ms10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
95 KB
21 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Platform
GitHub Pages
CDN
Cloudflare

Technology Stack

3 Technologies Detected

CSS Frameworks

1
Tailwind CSS

Analytics

1
Plausible Analytics

CDN

1
Cloudflare

SEO Analysis

D58/100
15
9
2
Meta Tags7/15
Content9/12
Headings3/8
Technical17/25
E-E-A-T3/7
Images2/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
O
opendefinition.orgopendefinition.org

The Open Definition - Open Definition - Defining Open in Open Data,...

The Open Definition - Open Definition - Defining Open in Open Data, Open Content and Open Knowledge

Title truncated.
Title Length99 chars

Recommended: 50-60 chars (~609px / 580px)

Description Length99 chars

Recommended: 120-160 chars

Issues (2)

  • • Title is too long (99 chars, ~609px). Will be truncated in search results.
  • • Missing H1 tag — every page should have exactly one H1

11 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

165 URLs

robots.txt

1 rules

Sitemap reference found

Allows all crawlers

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

D46/100
Bot Access
20/25
Machine Read.
13/25
Schema Data
0/25
Citation
13/25

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
blockquotesnav
Text ratio:7%
Words:339
Token eff.:Optimal
Sections/1K:2.9
Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary28w
Descriptive Headingsavg 3w
Canonical URL
Open Graph0/3
Twitter Card0/3
Language Tag
Publish Date
Author Info
Lists
Tables
TL;DR / Summary
About Page Link
Recommendations (8)
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.
B
73/100
9
Passed
3
Critical
0
Warnings
Images & Alt Text
15/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
18/20
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
9/15
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...
Upgrade to view recommendations

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.
65/100
A+
10 mg
CO₂e / view
95.1 KB
Page Weight
95%
Cleaner Than
New Visitor
11 mg
vs
Returning (cached)
6 mg
Annual (10K/mo)
1.2 kg
Emission Segments
Data Center
<0.001 g
Network
3 mg
Device
6 mg
Resource Breakdown
JavaScript
19.1 KB
Images
56.8 KB
CSS
10.1 KB
HTML
9.2 KB
Green Hosting Verified
Cloudflare
Provider Match
4 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
B

Security Score

71%Good
Static / Informational

HTTPS

WAF

65d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Google Trust Services

Key Algorithm

ECDSA (secp256r1) (256 bit)

Signature

ECDSA with SHA-256

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2+H3

Valid From

03.04.2026

Valid Until

02.07.2026

OCSP Stapling

Enabled

Subject Alternative Names (2)

opendefinition.org*.opendefinition.org

SHA-256 Fingerprint

05:32:16:CE:93:9D:8F:FE:1F:10:A8:BE:1A:B9:68:E0:5F:12:04:B0...

Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

access-control-allow-origin
*
age
0
alt-svc
h3=":443"; ma=86400
cache-control
🟡 600s(max-age=600)
cf-cache-status
DYNAMIC
cf-ray🇮🇹 Milan
9f358b2829d40e3e-MXP
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

0

SPF
DKIM
DMARC

Domain Information

opendefinition.org

Domain Age
19y 1m

Created

13.03.2007

Expires

13.03.2027

Last Updated

17.01.2026

Registrar

Gandi SAS

DNSSEC
Not Enabled

Privacy & Compliance

Cookie Consent Banner
Privacy Policy
Terms of Service

GDPR Indicators

Privacy policy page linked

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.
D
57/100
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=1.0
2 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

HK Grotesk

WCAG Partial
70/100
Readability
/30
17/30

12px · LH 1.50

Hierarchy
/20
20/20

4.62x ratio · ✓ H1→H6

WCAG
/25
17/25

1:1 min contrast

Performance
/25
16/25

1 font

Heading Font

HK Grotesk

Sans58px

Body Font

HK Grotesk

Sans12px

Contrast Ratio

1:1

6 issues

Reading Comfort

~43 CPL

Narrow lines
58px
h1
29px
h2
12px
p

❌ Critical: 12px body text is too small. Minimum 14px, recommend 16px+.

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

❌ Very complex text: Flesch score 20/100. Consider shorter sentences and simpler words.

⚠️ Partial contrast: 6 elements below WCAG AA threshold (min 1.0:1).

✅ Perfect heading hierarchy: Sequential h1→h2→h3 with single H1 — ideal for SEO & accessibility.

✅ Strong hierarchy: Headlines are 4.6x larger than body text.

Buy on MyFontsFlesch 20

Color Palette

6 unique colors
2.59:1 Fail Light
#f4f4f4
Background· 55.5%
#999999
Other· 4.1%
#01d1ff
Primary· 35.2%
#4ddbf6
Accent· 1.3%
#40cceb
Accent· 0.5%

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

2
PlausibleSMB
Google AnalyticsFree

User behavior and product analytics

1

Categories

2

Total Tools

0

Enterprise

0

Mid-Market

Assessment: Growing marketing technology adoption

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Scripts & Styles

8 Resources

4
Scripts
4
Styles
0
Async
1
Defer

Top Script Sources

local(2)plausible.io(1)a.okfn.org(1)

Website Identity

opendefinition.org

19 years old
Location detected: 🇨🇦 Canadavia ip
Gandi SASen

Sponsored

Last analyzed: 28 Apr 2026 at 10:57

Historical Analysis & Change Tracking