What does StackOptic analyze?

StackOptic runs 18 analysis modules on any public website from a single URL. It detects 7,000+ technologies (CMS, frameworks, analytics, payments, CDN, hosting), evaluates SSL certificates and HTTP security headers with grades from A+ to F, measures Core Web Vitals (LCP, CLS, TBT, FCP), audits SEO meta tags and structured data, checks email security (SPF, DKIM, DMARC), analyzes AI & LLM readiness including bot access and llms.txt validation, extracts color palettes and typography, estimates carbon footprint, and generates permanent shareable reports.

Does it work on sites behind Cloudflare or bot protection?

Yes. StackOptic uses a real browser engine that loads pages exactly like a human visitor — executing JavaScript, rendering CSS, and handling redirects. This allows it to bypass Cloudflare, LiteSpeed, Sucuri, and other bot protection systems where traditional crawlers and HTTP-only tools fail.

What do I get on the free plan?

The free plan includes 5 analyses per day with access to all 18 modules, full scores, technology detection, and security grades. Every report is permanently accessible via a unique shareable URL — no login required to view. No credit card needed. AI-powered insights, re-analysis, PDF/JSON export, and comparison features are available on Pro ($24/mo) and Agency ($99/mo) plans.

What is AI & LLM readiness analysis?

This module evaluates how visible and citable your website is to AI search engines like ChatGPT, Perplexity, Google AI Overviews, and Claude. It audits access permissions for 8 major AI bots, validates llms.txt and llms-full.txt files, scores citation-ready content structure, and analyzes structured data (JSON-LD) for GEO readiness — helping you rank in the next generation of search.

How long does an analysis take?

Most analyses complete in under 10 seconds. StackOptic runs all 18 modules in parallel using a real browser session, so you get technology detection, security audit, performance metrics, SEO analysis, and AI readiness scoring simultaneously.

How accurate are the results?

Detection is based on real browser execution — DOM inspection, JavaScript runtime analysis, HTTP headers, and DNS records. With 7,000+ technology signatures and Lighthouse-calibrated performance scoring, StackOptic achieves high accuracy for mainstream technologies.

What security checks are performed?

The security module evaluates SSL/TLS certificates, 12+ HTTP security headers (HSTS, CSP, X-Frame-Options, Permissions-Policy, Referrer-Policy), HTTPS enforcement, and email authentication (SPF, DKIM, DMARC). Each site receives a letter grade from A+ to F with specific remediation steps.

Do you store the websites I analyze?

StackOptic only stores publicly available information that any visitor to a website would see — HTML content, HTTP headers, DNS records, and screenshots. We do not access private data, log in to websites, or perform any intrusive testing.

Back to Search

cdnjs.com

https://cdnjs.com· First analyzed 20 Feb 2026· Updated 20 Feb 2026

Export

cdnjs.com

Mobile

Sponsored

Hosting Provider

Cloudflare

cloudflare.com

IP Address

104.24.196.20

Server Location

🇨🇦 Toronto, Canada

ASN

AS13335

Organization

Cloudflare, Inc.

Server

Cloudflare

CDN

Cloudflare

WAF

Cloudflare

Nameservers

ben.ns.cloudflare.com.lara.ns.cloudflare.com.

Performance

Page Speed

369 KB

23 requests

0–49

50–89

90–100

Architecture Stack

Hybrid

⚙️ SSR

Frontend

Framework

Nuxt.js

Infrastructure

Hosting

Cloudflare

CDN

Cloudflare

Technology Stack

5 Technologies Detected

Meta Frameworks

Libraries

Icon Libraries

Analytics

CDN

SEO Analysis

A84/100

cdnjs.comcdnjs.com

cdnjs - The #1 free and open source CDN built to make life easier f...

Simple. Fast. Reliable. Content delivery at its finest. cdnjs is a free and open-source CDN service trusted by over 12.5% of all websites, serving over 200 b...

Title truncated. Description truncated.

Title Length80 chars

Recommended: 50-60 chars

Description Length276 chars

Recommended: 120-160 chars

Issues (0)

2 issues found

Upgrade to view details

Crawlability

Sitemap

Type: standard

robots.txt

3 rules

Sitemap reference found

Allows all crawlers

Sponsored

Security Score

51%Poor

Interactive

HTTPS

WAF

68d

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

29.01.2026

Valid Until

29.04.2026

Subject Alternative Names (1)

cdnjs.com

SHA-256 Fingerprint

E5:AF:1B:9E:38:05:FD:3B:88:1C:35:D0:E1:C8:CF:77:E5:89:41:17...

Top Recommendations

Security recommendation preview

Upgrade to view recommendations

Upgrade to view header details

HTTP Headers

Developer Console

age

3360

cache-control

🟡 12 Hours(private, max-age=43200)

cf-cache-status

HIT

cf-ray🇩🇪 Frankfurt

9d0cb933fb5aa19f-FRA

content-encoding

⚡ Brotli(br)

content-type

text/html; charset=utf-8

Good Warning Issue

Email Infrastructure

Yandex Mail

Score

SPF

DKIM

DMARC

MX Records (1)

mx.yandex.net

Domain Information

cdnjs.com

Domain Age

15y 1m

Created

20.01.2011

Expires

20.01.2034

Last Updated

22.08.2024

Registrar

NameCheap, Inc.

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

Typography & Readability

Ubuntu

56/100

Readability

/30

30/40

16px · LH --

Hierarchy

/20

18/25

3x ratio

WCAG

/25

5/15

Contrast: undefined

Performance

/25

13/20

1 font

Heading Font

Ubuntu

Sans48px

Body Font

Ubuntu

Sans16px

Contrast Ratio

Reading Comfort

~39 CPL

Needs attention

48px

24px

16px

✅ Excellent readability: 16px body text is ideal for all devices.

✅ Strong hierarchy: Headlines are 3.0x larger than body text.

✅ Good performance: Using 1 font families keeps load times fast.

✅ Consistent design: Single font family with weight variations is a modern best practice.

✅ Smart font loading: Using font-display: swap prevents invisible text during load.

⚠️ Risky: Text appears on background images without overlay protection.

Buy on MyFonts

Business & Marketing Stack

1 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

12 Resources

Scripts

Styles

Async

Defer

Top Script Sources

local(9)api.radar.cloudflare.com(1)google-analytics.com(1)static.cloudflareinsights.com(1)

Website Identity

X (Twitter)GitHub

Sponsored

Last analyzed: 20 Feb 2026 at 08:44

Historical Analysis & Change Tracking