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pdf.io

https://pdf.io· First analyzed 24 May 2026· Updated 24 May 2026
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pdf.io
Desktop screenshot of pdf.io
Mobile screenshot of pdf.io
Mobile

Sponsored

Hosting Provider

Hetzner
hetzner.com

IP Address

148.251.196.27

Site Location

🇩🇪 Germanyvia ip

Server Location

🇩🇪 Falkenstein, Germany

ASN

AS24940

Organization

Apps Computer Software LLC

Server

Nginx

Nameservers

ns2.gcdn.services.ns1.gcorelabs.net.

Performance

100

Core Web Vitals

Weight

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

Architecture Stack

Monolithic
⚙️ SSR
Infrastructure
Hosting
Hetzner

Technology Stack

6 Technologies Detected

Analytics

2
Google Analytics
Google Analytics 4

Advertising

2
Google AdsGoogle AdSense

CSS Frameworks

1
Tailwind CSS

Web Servers

1
Nginx

SEO Analysis

D59/100
17
8
1
Meta Tags12/15
Content10/12
Headings0/8
Technical19/25
E-E-A-T2/7
Images0/7
Links5/5
URL5/5
Social0/5
Freshness0/4
Mobile3/4
Indexability3/3
P
pdf.iopdf.io

PDF.io – Essential Online PDF Tools

Free online PDF tools: convert, edit, merge, split, and compress in your browser. Fast, easy, and secure. No signup or installation required.

Title Length35 chars

Recommended: 50-60 chars (~204px / 580px)

Description Length141 chars

Recommended: 120-160 chars

Issues (1)

  • • Missing H1 tag — every page should have exactly one H1

9 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

320 URLs

robots.txt

15 rules

Sitemap reference found

Local SEO

Local Search Readiness

20/100
Needs Work
6 12

Sponsored

AI & LLM Readiness

F36/100
Bot Access
20/25
Machine Read.
8/25
Schema Data
2/25
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:3%
Words:730
Token eff.:Optimal
Depth:1/5

Structured Data

1 JSON-LD
Organization×1.1

Citation Readiness

Opening Summary218w
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 (11)
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.
D
59/100
9
Passed
4
Critical
2
Warnings
Images & Alt Text
20/20
Checks if images have descriptive alt text for screen readers and visually impaired users.
Semantic Structure
8/20
Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.
Forms & Inputs
5/15
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
7/15
Ensures all interactive elements are reachable and operable via keyboard (tab, enter, escape).
ARIA & Roles
4/15
Checks correct use of WAI-ARIA attributes (roles, states, properties) for assistive technologies.
4 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.
70/100
A
59 mg
CO₂e / view
585.8 KB
Page Weight
80%
Cleaner Than
New Visitor
68 mg
vs
Returning (cached)
34 mg
Annual (10K/mo)
7.1 kg
Emission Segments
Data Center
3 mg
Network
17 mg
Device
39 mg
Resource Breakdown
JavaScript
393.2 KB
Images
12.6 KB
CSS
137.6 KB
HTML
24.0 KB
Other
18.5 KB
Green Hosting Verified
Cloudflare
GWF Verified
3 recommendations
  • •Carbon footprint recommendation preview...
Upgrade to view recommendations
C

Security Score

65%Fair
Critical / Transactional

HTTPS

No WAF

15d

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

10.03.2026

Valid Until

08.06.2026

Subject Alternative Names (2)

*.pdf.iopdf.io

SHA-256 Fingerprint

C0:0D:D5:AF:32:B6:17:C8:B8:F2:28:56:03:61:B3:E6:41:18:C5:08...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

content-encoding
⚡ Brotli(br)
content-security-policy
frame-ancestors 'self'
content-type
text/html; charset=UTF-8
date
Sun, 24 May 2026 01:44:06 GMT
referrer-policy
origin-when-cross-origin
server
nginx
Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

80

SPF
DKIM
DMARC

DMARC Policy

Reject (Strictest)

Domain Information

pdf.io

Domain Age
10y 10m

Created

26.07.2015

Expires

26.07.2027

Last Updated

05.05.2026

Registrar

Porkbun LLC

DNSSEC
Not Enabled

Privacy & Compliance

Cookiebot

Cookie Consent Banner
Cookiebot
Privacy Policy
Terms of Service

GDPR Indicators

Cookie consent banner detected
CMP: Cookiebot

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 Friendly15 breakpoints
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, user-scalable=no
4 recommendations
  • •Mobile compatibility recommendation preview...
Upgrade to view recommendations

Typography & Readability

Rubik

WCAG AAA
68/100
Readability
/30
21/30

24px · LH --

Hierarchy
/20
8/20
WCAG
/25
21/25

9.79:1 min contrast

Performance
/25
18/25

1 font · 2 req

Heading Font

Rubik

Body Font

Rubik

Sans24px

Contrast Ratio

9.79:1

WCAG AAA (≥7:1)

Reading Comfort

Single Family

center aligned
24px
p

✅ Excellent readability: 24px body text is ideal for all devices.

✅ WCAG AAA contrast: All text meets 7:1 ratio (min 9.8:1).

✅ Lean font stack: 1 font families keeps load times fast.

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

Buy on MyFontsFlesch 58

Color Palette

5 unique colors
Light
#ffffff
Background· 86.5%
#101115
Primary· 6.499999999999999%
#aab9a9
Secondary· 2.7%
#51465b
Secondary· 1.5%

Business & Marketing Stack

2 Tools Detected

Advanced

Behavior Analytics

1
Google AnalyticsFree

User behavior and product analytics

Advertising

1
Google AdsEnterprise

Ad platforms and retargeting pixels

2

Categories

2

Total Tools

1

Enterprise

0

Mid-Market

Assessment: Well-developed marketing technology stack

Ad Networks

Google AdSense

Sponsored

Scripts & Styles

7 Resources

6
Scripts
1
Styles
2
Async
1
Defer

Top Script Sources

local(3)pagead2.googlesyndication.com(2)googletagmanager.com(1)

Website Identity

pdf.io

pdf.io

Organization
support@123apps.com
10 years old
Location detected: 🇩🇪 Germanyvia ip
Porkbun LLCen

Sponsored

Last analyzed: 24 May 2026 at 01:44

Historical Analysis & Change Tracking