docbook.org

https://docbook.org· First analyzed 28 Apr 2026· Updated 28 Apr 2026

Export

docbook.org

Mobile

Sponsored

Hosting Provider

Positive Infrastructure

IP Address

185.27.20.177

Site Location

🇬🇧 United Kingdomvia ip

Server Location

🇬🇧 London, United Kingdom

ASN

AS21260

Organization

Positive Infrastructure

Server

Nginx

Nameservers

ns3.dreamhost.com.ns1.dreamhost.com.ns2.dreamhost.com.

Performance

100

Core Web Vitals

Weight

First Contentful Paint

528 ms10%

Speed Index

686 ms10%

Largest Contentful Paint

—25%

Total Blocking Time

0.0 ms30%

Cumulative Layout Shift

0.00025%

1.3 MB

13 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Infrastructure

Hosting

Positive Infrastructure

Technology Stack

1 Technologies Detected

Web Servers

Nginxv1.22.1

SEO Analysis

D47/100

Meta Tags4/15

Content7/12

Headings6/8

Technical9/21

E-E-A-T0/7

Images4/7

Links5/5

URL5/5

Social0/5

Freshness0/4

Mobile4/4

Indexability3/3

docbook.orgdocbook.org

DocBook.org

No description available for this page.

Title Length11 chars

Recommended: 50-60 chars (~66px / 580px)

Description Length0 chars

Recommended: 120-160 chars

Issues (1)

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

9 issues found

Upgrade to view details

Local SEO

Local Search Readiness

0/100

Poor

15 2

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

Sponsored

AI & LLM Readiness

F36/100

Bot Access

20/25

Machine Read.

10/25

Schema Data

0/25

Citation

6/25

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

nav

Text ratio:36%

Words:141

Token eff.:Too Short

Depth:1/5

Structured Data

No Schema

Citation Readiness

Opening Summary28w

Descriptive Headings

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.

77/100

Passed

Critical

Warnings

Images & Alt Text

20/20

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

Semantic Structure

17/20

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.

63/100

134 mg

CO₂e / view

1.3 MB

Page Weight

70%

Cleaner Than

New Visitor

153 mg

Returning (cached)

76 mg

Annual (10K/mo)

16.0 kg

Emission Segments

Data Center

7 mg

Network

39 mg

Device

88 mg

Resource Breakdown

Images

164.4 KB

CSS

1.1 MB

HTML

1.5 KB

Green Hosting Verified

The Positive Internet Company Ltd.

GWF Verified

3 recommendations

•Carbon footprint recommendation preview...

Upgrade to view recommendations

Security Score

71%Good

Static / Informational

HTTPS

No WAF

34d

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/2

Valid From

03.03.2026

Valid Until

01.06.2026

Subject Alternative Names (1)

docbook.org

SHA-256 Fingerprint

E2:F5:EA:9C:06:BC:0C:3B:46:77:74:AF:C0:08:0B:4B:C2:72:FD:55...

Recommendations

Security recommendation preview

Upgrade to view recommendations

Upgrade to view header details

HTTP Headers

Developer Console

content-encoding

📦 Gzip(gzip)

content-type

text/html; charset=utf-8

date

Tue, 28 Apr 2026 14:53:44 GMT

etag

W/"69bc3d52-99d"

last-modified

Thu, 19 Mar 2026 18:15:46 GMT

server

nginx/1.22.1

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

MX Records (2)

mx1.mailchannels.net

mx2.mailchannels.net

Domain Information

docbook.org

Domain Age

27y 4m

Created

11.12.1998

Expires

10.12.2027

Last Updated

02.01.2026

Registrar

DreamHost, 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.

54/100

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

Cabin + EB Garamond

WCAG AA

75/100

Readability

/30

25/30

21px · LH 1.50

Hierarchy

/20

14/20

1.73x ratio · ✓ H1→H6

WCAG

/25

22/25

6.99:1 min contrast

Performance

/25

14/25

2 fonts · 9 req

Heading Font

Cabin

Sans37px

Body Font

EB Garamond

Serif21px

Contrast Ratio

6.99:1

WCAG AA (≥4.5:1)

Reading Comfort

Sans Headlines + Serif Body

left aligned

37px

21px

✅ Excellent readability: 21px body text is ideal for all devices.

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

✅ WCAG AA contrast: All text meets 4.5:1 ratio (min 7.0:1).

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

✅ Lean font stack: 2 font families keeps load times fast.

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

Buy on MyFontsFlesch 53

Color Palette

7 unique colors

Dark

#616573

Secondary· 2.8%

#fffff7

Primary· 57.3%

#49a3a4

Secondary· 24.799999999999994%

#d9e6e0

Secondary· 6.6%

#c5d4d2

Secondary· 3.3%

#87abac

Secondary· 3.2%

#7797a1

Secondary· 2%

Sponsored

Scripts & Styles

2 Resources

Scripts

Styles

Async

Defer

Top Script Sources

Website Identity

docbook.org

27 years old

Location detected: 🇬🇧 United Kingdomvia ip

DreamHost, LLC

Sponsored

Last analyzed: 28 Apr 2026 at 14:54

Historical Analysis & Change Tracking