finn.no

Readiness by lane

Green: finn.no. Thin bar: E-Commerce & Marketplaces peer median.

Priority fixes for finn.no

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

1. Priority 1 · Accelerate

   Static files cached for 30 days or more

   Observed: A same-site stylesheet or script was cacheable for 1200 seconds, short of the 30-day benchmark.

   Why it matters: Returning visitors and later page views reuse cached files instead of downloading them again.

   What to do: Give versioned (fingerprinted) CSS, JavaScript, fonts and images Cache-Control: public, max-age=31536000, immutable, and change the file name whenever the content changes.

   60% of E-Commerce & Marketplaces peers do this. Limit: Read from the homepage response only; other pages or regions may send different headers.

   Guide: Browser Caching Guide for Website Owners

2. Priority 2 · Accelerate

   Modern image formats in use

   Observed: The homepage had 20 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.

   47% of E-Commerce & Marketplaces peers do this.

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

3. Priority 3 · Harden

   HSTS kept for at least a year

   Observed: Strict-Transport-Security was sent with a max-age of 183 days, below the one-year benchmark.

   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.

   32% of E-Commerce & Marketplaces peers do this.

   Guide: HTTPS and TLS Guide for Website Owners

4. Priority 4 · Harden

   Content Security Policy present

   Observed: The homepage response did not include a Content-Security-Policy header.

   What to do: Start with Content-Security-Policy-Report-Only to see what would break, tighten the policy over a few weeks, then enforce it.

   48% of E-Commerce & Marketplaces peers do this.

   Guide: Payment Security and PCI DSS: What Website Owners Need to Know

What finn.no already does well

Practices fewer than half of E-Commerce & Marketplaces peers use.

• security.txt publishedsecurity.txt with a contact found.7.6% of peers
• Referrer-Policy setReferrer-Policy present.20% of peers
• DMARC policy enforces quarantine or rejectDMARC policy p=reject.39% of peers

What we saw

Homepage checked

https://www.finn.no/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

Google Trust Services, 90-day validity, expiring 2027-01-01

CDN or edge

Google edge

DNS operators

Google Cloud DNS

HSTS

max-age 183 days

DMARC policy

p=reject

Homepage HTML

174 KB, br

Images on homepage

20 (svg 7, jpg 6, png 1)

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 E-Commerce & Marketplaces sites

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• fashionspark.com77
• flooranddecor.com77
• game.es77

E-Commerce & Marketplaces readiness benchmark