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

doorkeeper.jp

https://doorkeeper.jp· First analyzed 20 Feb 2026· Updated 20 Feb 2026

Export

doorkeeper.jp

Sponsored

Hosting Provider

Build io, Inc.

IP Address

66.71.205.0

Server Location

🇺🇸 Dover, United States

ASN

AS17294

Organization

Build io, Inc.

Server

Envoy

Nameservers

ns1.dnsimple.com.ns2.dnsimple.com.ns3.dnsimple.com.ns4.dnsimple.com.

Performance

Page Speed

34 requests

Image Optimization

Lazy Load

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Infrastructure

Hosting

Build io, Inc.

Technology Stack

7 Technologies Detected

Analytics

Libraries

CSS Frameworks

Icon Libraries

Tag Managers

SEO Analysis

D58/100

doorkeeper.jpdoorkeeper.jp

セミナー・勉強会・イベント管理ツール | Doorkeeper

セミナーやイベントの開催も、集客も、集金も。Doorkeeperなら全部まとめて簡単に。

Title Length31 chars

Recommended: 50-60 chars

Description Length44 chars

Recommended: 120-160 chars

Issues (0)

5 issues found

Upgrade to view details

Crawlability

Sitemap

robots.txt

15 rules

Sitemap reference found

Sponsored

Security Score

61%Fair

Interactive

HTTPS

No WAF

64d

Certificate Details

Type

Domain Validated (DV)

Certificate Authority

Let's Encrypt

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.3

HTTP Protocol

HTTP/1.1

Valid From

26.01.2026

Valid Until

26.04.2026

Subject Alternative Names (1)

*.doorkeeper.jp

SHA-256 Fingerprint

15:2D:03:8C:0B:72:8E:51:A1:61:2F:89:50:C8:83:A4:2B:20:6E:50...

Top Recommendations

Security recommendation preview

Upgrade to view recommendations

Upgrade to view header details

HTTP Headers

Developer Console

cache-control

🟡 0s(max-age=0, private, must-revalidate)

content-encoding

📦 Gzip(gzip)

content-type

text/html; charset=utf-8

date

Fri, 20 Feb 2026 01:36:52 GMT

etag

W/"5ba3d8378eddd9664564021fd300b032"

referrer-policy

no-referrer-when-downgrade

Good Warning Issue

Email Infrastructure

Google Workspace

Score

SPF

DKIM

DMARC

DMARC Policy

Quarantine (Moderate)

MX Records (6)

aspmx2.googlemail.com

alt2.aspmx.l.google.com

aspmx.l.google.com

alt1.aspmx.l.google.com

+2 more

Domain Information

doorkeeper.jp

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

GDPR Indicators

Typography & Readability

-apple-system

95/100

Readability

/30

40/40

16px · LH 1.60

Hierarchy

/20

25/25

2.01x ratio

WCAG

/25

15/15

Contrast: undefined

Performance

/25

20/20

System fonts

Heading Font

-apple-system

Sans32px

Body Font

-apple-system

Sans16px

Contrast Ratio

Reading Comfort

~33 CPL

Needs attention

32px

16px

18px

16px

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

✅ Optimal line spacing: 1.60 ratio ensures comfortable reading.

✅ Strong hierarchy: Headlines are 2.0x larger than body text.

✅ Excellent performance: System fonts eliminate font loading delays (better LCP).

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

✅ Protected text on images: Using gradient for readability.

Business & Marketing Stack

4 Tools Detected

Advanced

Customer Support

Help ScoutSMB

Live chat and helpdesk tools

Behavior Analytics

MixpanelMid-Market

Google Tag ManagerFree

Google AnalyticsFree

User behavior and product analytics

Sponsored

Scripts & Styles

12 Resources

Scripts

Styles

Async

Defer

Top Script Sources

beacon-v2.helpscout.net(3)googletagmanager.com(3)doorkeeper.jp(2)google-analytics.com(1)cdn.mxpnl.com(1)

Sponsored

Last analyzed: 20 Feb 2026 at 01:37

Historical Analysis & Change Tracking