fsharp.org

https://fsharp.org· First analyzed 15 May 2026· Updated 15 May 2026

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fsharp.org

Mobile

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Hosting Provider

GitHub Pages

pages.github.com

IP Address

185.199.109.153

Site Location

🇺🇸 United Statesvia ip

Server Location

🇺🇸 San Francisco, United States

ASN

AS54113

Organization

GitHub, Inc

Server

GitHub.com

CDN

Fastly

Nameservers

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

Performance

100

Core Web Vitals

Weight

First Contentful Paint

681 ms10%

Speed Index

885 ms10%

Largest Contentful Paint

—25%

Total Blocking Time

0.0 ms30%

Cumulative Layout Shift

0.00025%

395 KB

23 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Frontend

Framework

Alpine.js

Styling

Tailwind CSS

Infrastructure

Platform

GitHub Pages

CDN

Fastly

Technology Stack

7 Technologies Detected

Analytics

Frameworks

UI Components

CSS Frameworks

Icon Libraries

Fonts

SEO Analysis

D55/100

Meta Tags4/15

Content12/12

Headings3/8

Technical15/25

E-E-A-T0/7

Images4/7

Links5/5

URL5/5

Social0/5

Freshness0/4

Mobile4/4

Indexability3/3

fsharp.orgfsharp.org

fsharp.org

No description available for this page.

Title Length10 chars

Recommended: 50-60 chars (~59px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (2)

• Missing meta description — important for click-through rates in SERPs
• Missing H1 tag — every page should have exactly one H1

10 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

38 URLs

robots.txt

2 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

F36/100

Bot Access

20/25

Machine Read.

9/25

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

code blocksnav

Text ratio:20%

Words:3,714

Token eff.:Good

Sections/1K:5.7

Depth:2/5

Structured Data

No Schema

Citation Readiness

Opening Summary15w

Descriptive Headingsavg 4.2w

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.

79/100

Passed

Critical

Warnings

Images & Alt Text

20/20

Checks if images have descriptive alt text for screen readers and visually impaired users.

Semantic Structure

13/20

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

7/15

Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.

3 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.

56/100

49 mg

CO₂e / view

394.7 KB

Page Weight

90%

Cleaner Than

New Visitor

56 mg

Returning (cached)

28 mg

Annual (10K/mo)

5.9 kg

Emission Segments

Data Center

11 mg

Network

12 mg

Device

26 mg

Resource Breakdown

JavaScript

102.7 KB

Images

73.7 KB

CSS

197.8 KB

Fonts

1.4 KB

HTML

19.2 KB

Green Hosting Not Verified

GitHub Pages

3 recommendations

•Carbon footprint recommendation preview...

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Security Score

71%Good

Static / Informational

HTTPS

No WAF

67d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/2

Valid From

22.04.2026

Valid Until

21.07.2026

Subject Alternative Names (2)

fsharp.orgwww.fsharp.org

SHA-256 Fingerprint

0E:69:4E:0B:39:89:87:3E:39:7D:D8:F2:B6:AA:8D:31:03:CE:F1:FC...

Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

accept-ranges

bytes

access-control-allow-origin

age

cache-control

🟡 600s(max-age=600)

content-encoding

📦 Gzip(gzip)

content-length

19356

Good Warning Issue

Email Infrastructure

Google Workspace

Score

SPF

DKIM

DMARC

MX Records (5)

alt4.aspmx.l.google.com

alt1.aspmx.l.google.com

aspmx.l.google.com

alt3.aspmx.l.google.com

+1 more

Domain Information

fsharp.org

Domain Age

13y 7m

Created

30.09.2012

Expires

30.09.2026

Last Updated

05.09.2025

Registrar

NameCheap, Inc.

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

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.

66/100

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

2 recommendations

•Mobile compatibility recommendation preview...

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Typography & Readability

Roboto Flex + Apple Color Emoji

WCAG Partial

52/100

Readability

/30

15/30

14px · LH 1.71

Hierarchy

/20

8/20

WCAG

/25

13/25

1:1 min contrast

Performance

/25

16/25

3 fonts · 2 req

Heading Font

Roboto Flex

Sans

Body Font

Apple Color Emoji

Sans14px

Contrast Ratio

1:1

31 issues

Reading Comfort

~39 CPL

Narrow lines

30px

24px

14px

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

⚠️ Hard to read: Flesch score 39/100. Simplify sentences for wider reach.

⚠️ Partial contrast: 31 elements below WCAG AA threshold (min 1.0:1).

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

✅ Smart font loading: font-display: swap prevents invisible text during load (FOIT).

GGoogle Fonts Buy on MyFontsFlesch 39

Color Palette

6 unique colors

17.58:1 AAA Dark

#191919

Text· 68.70000000000002%

#ffffff

Background· 19.2%

#378bba

Primary· 8%

#a5d1dc

Secondary· 1.4%

#425e6e

Secondary· 1.4%

#689bb5

Secondary· 1.2%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

13 Resources

Scripts

Styles

Async

Defer

Top Script Sources

cdn.jsdelivr.net(4)google-analytics.com(1)local(1)

Website Identity

fsharp.org

13 years old

Location detected: 🇺🇸 United Statesvia ip

NameCheap, Inc.📧 Google Workspaceen

Social Profiles

YouTube GitHub Discord Reddit

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Last analyzed: 15 May 2026 at 01:04

Historical Analysis & Change Tracking