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

fueleconomy.gov

https://fueleconomy.gov· First analyzed 16 Feb 2026· Updated 16 Feb 2026

Export

fueleconomy.gov

Sponsored

Hosting Provider

Oak Ridge National Laboratory

IP Address

160.91.94.41

Server Location

🇺🇸 Clinton, United States

ASN

AS50

Organization

Oak Ridge National Laboratory

Server

Microsoft IIS

Nameservers

ns4.ornl.gov.ns5.ornl.gov.ns6.ornl.gov.ns7.ornl.gov.+2 more

Performance

Page Speed

1.2 MB

35 requests

0–49

50–89

90–100

Architecture Stack

Monolithic

⚙️ SSR

Frontend

Styling

Bootstrap

Infrastructure

Hosting

Oak Ridge National Laboratory

Technology Stack

7 Technologies Detected

Libraries

CSS Frameworks

Analytics

Web Servers

SEO Analysis

B70/100

fueleconomy.govfueleconomy.gov

Fuel Economy

EPA gas mileage, safety, air pollution, and greenhouse gas estimates for new and used cars and trucks. Improve the MPG of your vehicle with our gas mileage t...

Description truncated.

Title Length12 chars

Recommended: 50-60 chars

Description Length161 chars

Recommended: 120-160 chars

Issues (0)

4 issues found

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Security Score

56%Poor

Interactive

HTTPS

No WAF

320d

Certificate Details

Type

Organization Validated (OV)

Certificate Authority

Internet2

Key Algorithm

RSA (2048 bit)

Signature

SHA-256 with RSA

TLS Version

TLSv1.2

HTTP Protocol

HTTP/2+H3

Valid From

02.12.2025

Valid Until

02.01.2027

OCSP Stapling

Enabled

Subject Alternative Names (4)

www.fueleconomy.govfueleconomy.govmpg3.dmz.ornl.govmpg4.dmz.ornl.gov

SHA-256 Fingerprint

3D:68:5C:1F:FD:94:CE:26:4C:AD:4F:66:7E:CB:CE:C0:0E:49:B8:D4...

Top Recommendations

Security recommendation preview

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Upgrade to view header details

HTTP Headers

Developer Console

alt-svc

h3=":443"; ma=86400; persist=1;

content-encoding

📦 Gzip(gzip)

content-length

11593

content-security-policy

'frame-ancestors' 'self'

content-type

text/html

date

Mon, 16 Feb 2026 23:30:21 GMT

Good Warning Issue

Email Infrastructure

Custom Mail Server

Score

SPF

DKIM

DMARC

DMARC Policy

Reject (Strictest)

MX Records (2)

MTA02.ORNL.gov

MTA01.ORNL.gov

Domain Information

fueleconomy.gov

Domain Age

26y 5m

Created

02.09.1999

Expires

31.07.2026

Last Updated

05.08.2025

Registrar

get.gov

DNSSEC

Not Enabled

Privacy & Compliance

Cookie Consent Banner

Typography & Readability

Helvetica Neue + verdana

75/100

Readability

/30

20/40

11px · LH 1.43

Hierarchy

/20

20/25

1.81x ratio

WCAG

/25

15/15

Contrast: undefined

Performance

/25

20/20

System fonts

Heading Font

Helvetica Neue

Sans20px

Body Font

verdana

Sans11px

Contrast Ratio

Reading Comfort

~53 CPL

Optimal (45–75)

20px

16px

11px

❌ Critical: 11px body text is too small. Increase to at least 14px.

✅ Optimal line spacing: 1.43 ratio ensures comfortable reading.

✅ Good hierarchy: Clear distinction between headlines and body text.

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

✅ Optimal line length: ~53 characters per line is comfortable to read.

✅ Clean layout: Consistent left alignment throughout.

Business & Marketing Stack

2 Tools Detected

Growing

Behavior Analytics

Google AnalyticsFree

Google Tag ManagerFree

User behavior and product analytics

Sponsored

Scripts & Styles

14 Resources

Scripts

Styles

Async

Defer

Top Script Sources

local(4)dap.digitalgov.gov(2)code.jquery.com(2)googletagmanager.com(1)netdna.bootstrapcdn.com(1)

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Last analyzed: 16 Feb 2026 at 23:30

Historical Analysis & Change Tracking