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zentralblatt-math.org

https://zentralblatt-math.org· First analyzed 20 May 2026· Updated 20 May 2026

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Mobile

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Hosting Provider

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

IP Address

141.66.194.5

Site Location

🇩🇪 Germanyvia ip

Server Location

🇩🇪 Eggenstein-Leopoldshafen, Germany

ASN

AS13040

Organization

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

Server

Cloudflare

CDN

Cloudflare

WAF

Cloudflare

Nameservers

dns1.fiz-karlsruhe.de.dns2.fiz-karlsruhe.de.

Performance

100

Core Web Vitals

Weight

First Contentful Paint

653 ms10%

Speed Index

849 ms10%

Largest Contentful Paint

—25%

Total Blocking Time

0.0 ms30%

Cumulative Layout Shift

0.00025%

191 KB

26 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Frontend

Styling

Bootstrap

Infrastructure

Hosting

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

CDN

Cloudflare

Technology Stack

7 Technologies Detected

Libraries

CSS Frameworks

UI Components

CDN

Customer Support

SEO Analysis

C63/100

Meta Tags7/15

Content12/12

Headings3/8

Technical16/21

E-E-A-T5/7

Images4/7

Links5/5

URL5/5

Social0/5

Freshness0/4

Mobile3/4

Indexability3/3

zentralblatt-math.orgzentralblatt-math.org

Documents Search - zbMATH Open

No description available for this page.

Title Length30 chars

Recommended: 50-60 chars (~194px / 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

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Local SEO

Local Search Readiness

11/100

Poor

3 14 1

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

D42/100

Bot Access

20/25

Machine Read.

11/25

Schema Data

2/25

Citation

9/25

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:7%

Words:1,002

Token eff.:Optimal

Sections/1K:3

Depth:1/5

Structured Data

1 JSON-LD

Organization×1.1

Citation Readiness

Opening Summary28w

Descriptive Headingsavg 1w

Canonical URL

Open Graph0/3

Twitter Card0/3

Language Tag

Publish Date

Author Info

Lists

Tables

TL;DR / Summary

About Page Link

Recommendations (9)

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.

65/100

Passed

Critical

Warnings

Images & Alt Text

20/20

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

Semantic Structure

16/20

Evaluates proper use of HTML5 semantic elements (header, nav, main, footer) and heading hierarchy.

Forms & Inputs

2/15

Verifies form fields have labels, error messages are clear, and inputs are properly associated.

Color & Contrast

14/15

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

6/15

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

2 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.

55/100

A+

24 mg

CO₂e / view

191.2 KB

Page Weight

95%

Cleaner Than

New Visitor

27 mg

Returning (cached)

14 mg

Annual (10K/mo)

2.8 kg

Emission Segments

Data Center

5 mg

Network

6 mg

Device

13 mg

Resource Breakdown

JavaScript

68.6 KB

Images

49.1 KB

CSS

64.7 KB

HTML

8.8 KB

Green Hosting Not Verified

FIZ Karlsruhe - Leibniz Institute Information Infrastructure

4 recommendations

•Carbon footprint recommendation preview...

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Security Score

41%Poor

Interactive

HTTPS

WAF

37d

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

Valid From

29.03.2026

Valid Until

27.06.2026

OCSP Stapling

Enabled

Subject Alternative Names (2)

zbmath.org*.zbmath.org

SHA-256 Fingerprint

70:04:DD:16:C7:67:E2:E6:87:92:5A:EF:E7:5A:62:07:D5:95:07:AB...

Top Recommendations

Security recommendation preview

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HTTP Headers

Developer Console

cf-cache-status

DYNAMIC

cf-ray🇦🇹 Vienna

9fed4bc0beab5b2b-VIE

content-encoding

📦 Gzip(gzip)

content-type

text/html; charset=utf-8

date

Wed, 20 May 2026 18:10:03 GMT

server

cloudflare

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

MX Records (1)

smtp.fiz-karlsruhe.de

Domain Information

zentralblatt-math.org

Domain Age

22y 5m

Created

01.12.2003

Expires

01.12.2026

Last Updated

03.04.2026

Registrar

united-domains GmbH

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

GDPR Indicators

Cookie consent banner detected

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, minimum-scale=0.1, maximum-scale=5.0

1 recommendation

•Mobile compatibility recommendation preview...

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Typography & Readability

Arimo

WCAG AAA

69/100

Readability

/30

18/30

15px · LH 1.33

Hierarchy

/20

15/20

1x ratio · ✓ H1→H6

WCAG

/25

23/25

8.58:1 min contrast

Performance

/25

13/25

1 font · 2 req

Heading Font

Arimo

Sans15px

Body Font

Arimo

Sans15px

Contrast Ratio

8.58:1

WCAG AAA (≥7:1)

Reading Comfort

~35 CPL

Narrow lines

15px

Minor Second

Scale

⚠️ Small text: 15px may strain on mobile. Use ≥16px for WCAG compliance.

⚠️ Tight line spacing (1.33). Increase to 1.4–1.6 for better readability.

❌ Very complex text: Flesch score 5/100. Consider shorter sentences and simpler words.

✅ WCAG AAA contrast: All text meets 7:1 ratio (min 8.6:1).

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

⚠️ Weak hierarchy: Headlines should be ≥2x body size for clear visual structure.

Buy on MyFontsFlesch 5

Color Palette

8 unique colors

3.98:1 AA Large Light

#ffffff

Background· 89.9%

#907987

Secondary· 1.4%

#d2dee4

Secondary· 1%

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

16 Resources

Scripts

Styles

Async

Defer

Top Script Sources

static.zbmath.org(7)local(2)

Website Identity

zentralblatt-math.org

22 years old

Location detected: 🇩🇪 Germanyvia ip

united-domains GmbHen

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Last analyzed: 20 May 2026 at 18:10

Historical Analysis & Change Tracking