Website readiness profile · Snapshot 23 October 2026
25ans.jp
25ans.jp's public homepage, certificate and DNS checked against 31 practices and compared with 3,856 News & Media sites.
- Readiness index
- 77/100
- Ahead of
- 82%
- Practices observed
- 22/31
- Popularity band
- Top 50K
News & Media median 68
of measured News & Media sites
0 of 31 could not be measured
Chrome UX Report top-sites list
Readiness by lane
Green: 25ans.jp. Thin bar: News & Media peer median.
Enable
87/100
Peers 89
Harden
69/100
Peers 56
Accelerate
85/100
Peers 68
Recover
0/100
Peers 11
Priority fixes for 25ans.jp
Ordered by impact and by how common each practice is among peers.
Priority 1 · Accelerate
Modern image formats in use
Observed: The homepage had 92 images and none used WebP or AVIF.
Why it matters: WebP and AVIF are typically much smaller than JPEG or PNG at similar quality, and images are often the heaviest part of a page.
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.
44% of News & Media peers do this. Limit: Based on the homepage HTML delivered to an automated client; scripts that run later were not executed.
Guide: AVIF, WebP, JPEG, and PNG: Choose the Right Image Format
Priority 2 · Harden
DMARC policy enforces quarantine or reject
Observed: No DMARC record was found at _dmarc.25ans.jp.
What to do: Publish DMARC with p=none and a reporting address first, fix any legitimate senders that fail SPF or DKIM alignment, then move to quarantine and finally reject.
37% of News & Media peers do this.
Priority 3 · Enable
Social preview image set
Observed: The homepage had no og:image, so shared links may show without a preview image.
What to do: Add Open Graph tags, including og:image with a 1200 x 630 image.
71% of News & Media peers do this.
Priority 4 · Harden
Certificate lifetime of 100 days or less
Observed: The certificate from GlobalSign nv-sa had a 198-day validity period, longer than the 100-day maximum that applies from March 2027.
What to do: Move to automated issuance and renewal now, while you still have time to test it.
66% of News & Media peers do this.
What 25ans.jp already does well
Practices fewer than half of News & Media peers use.
- Referrer-Policy setReferrer-Policy present.22% of peers
- Content Security Policy presentContent-Security-Policy present.29% of peers
- HSTS kept for at least a yearHSTS with a 365-day max-age covering subdomains.35% of peers
What we saw
- Homepage checked
- https://www.25ans.jp/
- Homepage response
- HTTP 200
- TLS
- TLSv1.3, HTTP/2
- Certificate
- GlobalSign, 198-day validity, expiring 2027-04-18
- Platform or framework
- Next.js
- DNS operators
- 1 self-run or other nameserver domain
- HSTS
- max-age 365 days, includeSubDomains
- Homepage HTML
- 711 KB, gzip
- Images on homepage
- 92 (jpg 211, png 65, svg 10)
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
Not observed 9
Observed 22
- HTTP requests move to HTTPS
- HSTS kept for at least a year
- TLS 1.3 negotiated
- Certificate has more than 14 days left
- X-Content-Type-Options: nosniff
- Framing restricted
- Content Security Policy present
- Referrer-Policy set
- HTTP/2 negotiated
- HTTP/3 advertised
- HTML compressed
- Static files cached for 30 days or more
- Offscreen images lazy-loaded
- No render-blocking scripts in <head>
- robots.txt published
- XML sitemap discoverable
- Canonical URL declared
- Meta description written
- Mobile viewport configured
- Structured data present
- Page language declared
- At most one redirect to the homepage
Own 25ans.jp?
Re-run the checks after a change, or verify the site in a free workspace to save reports with history, compare against similar sites and competitors, and track a private action plan. What owners get.
Live status for this site: Status Is Down: 25ans.jp. This profile covers configuration only.