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.

Technology Comparison

Sailthru vs Mailchimp

Side-by-side comparison based on real-world adoption data from 522 detections across analyzed websites.

Market Share Distribution

Sailthru (4%)Mailchimp (96%)

Total Detections

Sailthru

500

Mailchimp

HIGHER

Websites Using

Sailthru

500

Mailchimp

HIGHER

Used Together

websites use both

Sailthru

Email Marketing

22 detections

22 sites

Visit Website View Profile

Mailchimp

Email Marketing

All-in-one marketing platform with email campaigns, automation, landing pages, and CRM. Used by 13M+ businesses worldwide.

500 detections

500 sites

Visit Website View Profile

Our Analysis

Mailchimp is significantly more popular than Sailthru in our dataset, appearing on 500 websites compared to 22. Both are in the Email Marketing category, making them direct alternatives.

Sites Using Both (0)

No sites use both technologies together.

Only Sailthru

amny.com bobvila.com golf.com insidethemagic.net kark.com keloland.com kob.com kstp.com longislandpress.com ms.now

Only Mailchimp

20min.ch 20thcenturystudios.com 40billion.com 8theme.com aawsat.com acea.auto aceee.org acmethemes.com additudemag.com advocate.com

Frequently Asked Questions

What is the difference between Sailthru and Mailchimp?

Sailthru is a cross-channel marketing platform that enables businesses to send personalized email campaigns, manage customer data, and optimize engagement strategies. It focuses on delivering relevant content to users based on their behavior and preferences. All-in-one marketing platform with email campaigns, automation, landing pages, and CRM. Used by 13M+ businesses worldwide. Both belong to the Email Marketing category, making them direct alternatives.

Which is more popular, Sailthru or Mailchimp?

Based on our analysis of real websites, Mailchimp is more widely adopted with 500 detections compared to Sailthru's 22.

Can Sailthru and Mailchimp be used together?

In our current dataset, no websites use both technologies simultaneously. This suggests they typically serve as alternatives rather than complementary tools.

Check Any Website's Technology Stack

Find out if a website uses Sailthru, Mailchimp, or any other technology.

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