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htmlpurifier.org

https://htmlpurifier.org· First analyzed 26 Apr 2026· Updated 26 Apr 2026
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htmlpurifier.org
Desktop screenshot of htmlpurifier.org
Mobile screenshot of htmlpurifier.org
Mobile

Sponsored

Hosting Provider

Massachusetts Institute of Technology

IP Address

18.4.86.46

Site Location

🇺🇸 United Statesvia ip

Server Location

🇺🇸 Cambridge, United States

ASN

AS3

Organization

Massachusetts Institute of Technology

Server

Apache

Nameservers

dns1.registrar-servers.com.dns2.registrar-servers.com.

Performance

98

Core Web Vitals

Weight

First Contentful Paint
947 ms10%
Speed Index
1.2 s10%
Largest Contentful Paint
—25%
Total Blocking Time
0.0 ms30%
Cumulative Layout Shift
0.00025%
31 KB
10 requests
0–49
50–89
90–100

Architecture Stack

Monolithic
⚙️ SSR
SilverStripe

Technology Stack

1 Technologies Detected

Web Servers

1
Apache

SEO Analysis

C63/100
17
7
1
Meta Tags12/15
Content11/12
Headings8/8
Technical8/21
E-E-A-T3/7
Images4/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile4/4
Indexability3/3
H
htmlpurifier.orghtmlpurifier.org

HTML Purifier - Filter your HTML the standards-compliant way!

HTML filter that guards against XSS and ensures standards-compliant output.

Title Length61 chars

Recommended: 50-60 chars (~374px / 580px)

Description Length75 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing viewport meta tag — page may not be mobile-friendly (Google uses mobile-first indexing)

8 issues found

Upgrade to view details

Local SEO

Local Search Readiness

6/100
Poor
2 13 2

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

Sponsored

AI & LLM Readiness

D45/100
Bot Access
20/25
Machine Read.
14/25
Schema Data
0/25
Citation
11/25

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
blockquotescode blocks
Text ratio:40%
Words:792
Token eff.:Optimal
Sections/1K:15.2
Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary94w
Descriptive Headingsavg 1.5w
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...
Upgrade to view recommendations

Sponsored

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
74/100
10
Passed
3
Critical
0
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
14/20
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.
1 recommendation
  • •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.
50/100
A+
4 mg
CO₂e / view
31.5 KB
Page Weight
95%
Cleaner Than
New Visitor
5 mg
vs
Returning (cached)
2 mg
Annual (10K/mo)
468 g
Emission Segments
Data Center
<0.001 g
Network
<0.001 g
Device
2 mg
Resource Breakdown
JavaScript
876 B
Images
597 B
CSS
17.2 KB
HTML
12.9 KB
Green Hosting Not Verified
Massachusetts Institute of Technology
5 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
F

Security Score

0%Critical

No SSL

No WAF

N/A

Upgrade to view header details

HTTP Headers

Developer Console

accept-ranges
bytes
connection
Keep-Alive
content-length
12878
content-type
text/html
date
Sun, 26 Apr 2026 12:11:26 GMT
keep-alive
timeout=15, max=1000
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

45

SPF
DKIM
DMARC

MX Records (5)

eforward3.registrar-servers.com
eforward5.registrar-servers.com
eforward2.registrar-servers.com
eforward1.registrar-servers.com

+1 more

Domain Information

htmlpurifier.org

Domain Age
19 years

Created

10.04.2007

Expires

10.04.2027

Last Updated

16.03.2026

Registrar

NameCheap, Inc.

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.
F
35/100
Not 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.
3 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Georgia

WCAG Partial
61/100
Readability
/30
18/30

14px · LH 1.40

Hierarchy
/20
15/20

2.4x ratio · ✓ H1→H6

WCAG
/25
14/25

2.75:1 min contrast

Performance
/25
14/25

1 font

Heading Font

Georgia

Serif34px

Body Font

Georgia

Serif14px

Contrast Ratio

2.75:1

11 issues

Reading Comfort

~44 CPL

Narrow lines
34px
h1
28px
h2
28px
h3
14px
p

⚠️ Small text: 14px may strain on mobile. Use ≥16px for WCAG compliance.

✅ Optimal line spacing: 1.40 ratio (ideal range 1.4–1.6).

⚠️ Hard to read: Flesch score 49/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 11 elements below WCAG AA threshold (min 2.8:1).

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

✅ Strong hierarchy: Headlines are 2.4x larger than body text.

Buy on MyFontsFlesch 49

Color Palette

9 unique colors
Light
#e2e5e7
Secondary· 3.8%
#faf9ff
Primary· 42.20000000000001%
#496281
Secondary· 29.400000000000002%
#84ad8c
Secondary· 6.7%
#87989c
Secondary· 6.4%
#5c8084
Secondary· 4.6%
#426e4b
Secondary· 3.7%
#8e7892
Secondary· 2.5%

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

3 Resources

1
Scripts
2
Styles
0
Async
1
Defer

Top Script Sources

local(1)

Website Identity

htmlpurifier.org

19 years old
Location detected: 🇺🇸 United Statesvia ip
NameCheap, Inc.en

Social Profiles

GitHub

Sponsored

Last analyzed: 26 Apr 2026 at 12:11

Historical Analysis & Change Tracking