carused.jp

Readiness by lane

Green: carused.jp. Thin bar: Cars & Automotive peer median.

Priority fixes for carused.jp

Ordered by impact and by how common each practice is among peers.

1. Priority 1 · Harden

   HSTS kept for at least a year

   Observed: The homepage response did not include a Strict-Transport-Security header.

   Why it matters: HSTS tells browsers to use HTTPS for your host on every later visit, which removes the window where a first HTTP request can be intercepted.

   What to do: Send Strict-Transport-Security on HTTPS responses. Start with a short max-age (for example 300 seconds), confirm every subdomain works over HTTPS, then raise it in steps to 31536000. Add includeSubDomains only when all subdomains are HTTPS. HSTS preload is optional and hard to undo; hstspreload.org itself does not recommend it by default.

   On Next.js: Add the header in the headers() option of next.config.js for all routes.

   41% of Cars & Automotive peers do this. Limit: Read from the homepage response only; other pages or regions may send different headers.

   Guide: HTTPS and TLS Guide for Website Owners

2. Priority 2 · Accelerate

   Modern image formats in use

   Observed: The homepage had 135 images and none used WebP or AVIF.

   What to do: Serve WebP or AVIF with a JPEG or PNG fallback, either through an image CDN or by generating both formats at build time.

   On Next.js: The next/image component serves optimized formats automatically.

   47% of Cars & Automotive peers do this.

   Guide: AVIF, WebP, JPEG, and PNG: Choose the Right Image Format

3. Priority 3 · Accelerate

   No render-blocking scripts in <head>

   Observed: The homepage <head> loaded 1 external script without async or defer.

   What to do: Add defer to scripts that need the DOM, async to independent ones such as analytics, or move them to the end of the body.

   On Next.js: Use the next/script component with an appropriate loading strategy.

   45% of Cars & Automotive peers do this.

   Guide: Control Third-Party Scripts Before They Control Your Page

4. Priority 4 · Harden

   Framing restricted

   Observed: The homepage did not send frame-ancestors or X-Frame-Options, so other sites may frame it.

   What to do: Send Content-Security-Policy: frame-ancestors 'self' (or a list of trusted origins). X-Frame-Options: SAMEORIGIN covers older browsers.

   On Next.js: Add it in next.config.js headers().

   55% of Cars & Automotive peers do this.

   Guide: A Practical Website Health Check for Owners

What carused.jp already does well

Practices fewer than half of Cars & Automotive peers use.

• DMARC policy enforces quarantine or rejectDMARC policy p=quarantine.41% of peers

What we saw

Homepage checked

https://carused.jp/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

Amazon, 197-day validity, expiring 2027-01-14

Platform or framework

Next.js

DNS operators

Amazon Route 53

DMARC policy

p=quarantine

Homepage HTML

888 KB, gzip

Images on homepage

135 (jpg 74, svg 21, png 18)

Limits: homepage only, one location, one moment. Header checks reflect the homepage response; other pages may differ.

Stack and providers

Seen in the homepage response, certificate and DNS. Provider pages compare how their customers configure the same checks.

All 31 checks

Select a gap for the method and fix. How each check works

Compare with other Cars & Automotive sites

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• autoviny.sk62
• bardiauto.hu62
• kavak.com62
• lkq.cz62

Cars & Automotive readiness benchmark