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.

Web Fonts & Icon Libraries

See which font services and icon libraries websites use. Google Fonts, Adobe Fonts, Font Awesome, and more.

24 technologies in this category

Google Fonts

Free library of 1,500+ open-source font families served via Google's global CDN. Used by 42M+ websites worldwide.

3351 sites detectedfonts.google.com

Font Awesome

Internet's most popular icon library with 26,000+ icons in 67 categories. Available as web fonts, SVGs, and React components.

2673 sites detectedfontawesome.com

Material Icons

692 sites detected

Adobe Fonts (Typekit)

654 sites detected

Adobe Fonts

Premium font service included with Adobe Creative Cloud subscriptions. Offers 20,000+ fonts from world-class foundries.

441 sites detectedfonts.adobe.com

Ionicons

Ionicons is an open-source icon set crafted for web, iOS, Android, and desktop apps.

49 sites detectedionicons.com

Heroicons

5 sites detected

Feather Icons

4 sites detected

Bootstrap Icons

Bootstrap Icons is a growing library of SVG icons that are designed by @mdo and maintained by the Bootstrap Team.

icons.getbootstrap.com

Bunny Fonts

Bunny Fonts is an open-source, privacy-first web font platform designed to put privacy back into the internet.

fonts.bunny.net

Cufon

Cufon is a tool used to overlap real text with an image.

cufon.shoqolate.com

Emfont

Emfont is an open-source CJK webfont service that enables self-hosted, cache-efficient, and privacy-conscious distribution of open-source fonts.

font.emtech.cc

FontServer

FontServer is a online font delivery network service-provider for websites.

fontserver.ir

Fork Awesome

Fork Awesome is now a community effort based on Font Awesome by Dave Gandy.

forkaweso.me

Glyphicons

Glyphicons are icon fonts which you can use in your web projects.

glyphicons.com

Google Font API

Google Font API is a web service that supports open-source font files that can be used on your web designs.

fonts.google.com

Hoefler&Co

Hoefler&Co is a digital type foundry (font design studio) in Woburn, Massachusetts (formerly New York City), founded by type designer Jonathan Hoefler. Hoefler&Co designs typefaces for clients and for retail on its website.

typography.com

Lucide

Lucide is an open-source icon library that provides 1000+ vector (svg) files for displaying icons and symbols in digital and non-digital projects.

lucide.dev

MyFonts

MyFonts is a digital fonts distributor, based in Woburn, Massachusetts.

myfonts.com

Symbolset

Symbolset is a tool that converts words into icons by utilizing font technology, enabling visual representation of text-based content for various applications.

symbolset.com

Twitter Emoji (Twemoji)

Twitter Emoji is a set of open-source emoticons and emojis for Twitter, TweetDeck, and also for Android and iOS versions of the application.

twitter.github.io

Typekit

Typekit is an online service which offers a subscription library of fonts.

typekit.com

i30con

i30con is an icon toolkit based on CSS and JavaScript.

30nama.com

sIFR

sIFR is a JavaScript and Adobe Flash dynamic web fonts implementation.

mikeindustries.com