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.

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irs.gov

https://irs.gov· First analyzed 10 Feb 2026· Updated 10 Feb 2026

Export

irs.gov

Mobile

Sponsored

Hosting Provider

Internal Revenue Service

IP Address

152.216.11.110

Server Location

🇺🇸 New York, United States

ASN

AS30313

Organization

Internal Revenue Service

CDN

Cloudflare

WAF

Cloudflare

Nameservers

ns0022.secondary.cloudflare.com.ns0227.secondary.cloudflare.com.

Performance

Page Speed

1.1 MB

50 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Infrastructure

Hosting

Internal Revenue Service

CDN

Cloudflare

Technology Stack

6 Technologies Detected

Analytics

Libraries

CSS Frameworks

Icon Libraries

Tag Managers

SEO Analysis

A80/100

irs.govirs.gov

Internal Revenue Service | An official website of the United States...

Pay your taxes. Get your refund status. Find IRS forms and answers to tax questions. We help you understand and meet your federal tax responsibilities.

Title truncated.

Title Length78 chars

Recommended: 50-60 chars

Description Length151 chars

Recommended: 120-160 chars

Issues (0)

3 issues found

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Sponsored

Security Score

56%Poor

Interactive

HTTPS

No WAF

54d

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

cache-control

🔵 1 Days(public, max-age=86400)

content-encoding

⚡ Brotli(br)

content-language

content-length

15911

content-type

text/html; charset=UTF-8

date

Tue, 10 Feb 2026 23:10:25 GMT

Good Warning Issue

Typography & Readability

Source Sans Pro

72/100

Readability

/30

24/40

14px · LH 1.20

Hierarchy

/20

25/25

2x ratio

WCAG

/25

15/15

Contrast: undefined

Performance

/25

13/20

1 font

Heading Font

Source Sans Pro

Sans28px

Body Font

Source Sans Pro

Sans14px

Contrast Ratio

Reading Comfort

~50 CPL

Optimal (45–75)

28px

21px

19px

14px

⚠️ Small text: 14px may be hard to read on mobile. Consider 16px+.

✅ Strong hierarchy: Headlines are 2.0x 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.

✅ Optimal line length: ~50 characters per line is comfortable to read.

⚠️ Cramped layout: 46 elements lack adequate spacing.

Buy on MyFonts

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

Google Tag ManagerFree

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

21 Resources

Scripts

Styles

Async

Defer

Top Script Sources

local(6)googletagmanager.com(4)static.addtoany.com(3)dap.digitalgov.gov(2)resources.digital-cloud-gov.medallia.com(2)

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Last analyzed: 10 Feb 2026 at 23:10

Historical Analysis & Change Tracking