Website readiness profile · Snapshot 23 October 2026
skylark.co.jp
skylark.co.jp's public homepage, certificate and DNS checked against 31 practices and compared with 343 Uncategorized sites.
- Readiness index
- 58/100
- Ahead of
- 38%
- Practices observed
- 17/31
- Popularity band
- Top 5K
Uncategorized median 62
of measured Uncategorized sites
0 of 31 could not be measured
Chrome UX Report top-sites list
Readiness by lane
Green: skylark.co.jp. Thin bar: Uncategorized peer median.
Enable
100/100
Peers 80
Harden
48/100
Peers 54
Accelerate
33/100
Peers 58
Recover
100/100
Peers 12
Priority fixes for skylark.co.jp
Ordered by impact and by how common each practice is among peers.
Priority 1 · Accelerate
HTML compressed
Observed: The homepage HTML (33 KB) was delivered without gzip, Brotli or zstd compression.
Why it matters: Compression usually shrinks HTML several times over, so the first bytes of the page arrive sooner on slow connections.
What to do: Enable Brotli or gzip for text responses (HTML, CSS, JavaScript, JSON, SVG) at the CDN or origin.
On Amazon CloudFront: Enable Compress objects automatically on the cache behaviour.
92% of Uncategorized peers do this. Limit: Read from the homepage response only; other pages or regions may send different headers.
Guide: How to Set a Website Performance Budget That Teams Can Keep
Priority 2 · Harden
HSTS kept for at least a year
Observed: The homepage response did not include a Strict-Transport-Security header.
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 Amazon CloudFront: Attach a response headers policy with Strict-Transport-Security to each distribution.
34% of Uncategorized peers do this.
Priority 3 · Accelerate
Static files cached for 30 days or more
Observed: A same-site stylesheet or script was cacheable for 300 seconds, short of the 30-day benchmark.
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.
44% of Uncategorized peers do this.
Priority 4 · Accelerate
No render-blocking scripts in <head>
Observed: The homepage <head> loaded 10 external scripts 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.
37% of Uncategorized peers do this.
Guide: Control Third-Party Scripts Before They Control Your Page
What skylark.co.jp already does well
Practices fewer than half of Uncategorized peers use.
- Nameservers spread across providersNameservers spread across more than one operator.12% of peers
- Modern image formats in useWebP or AVIF images detected.33% of peers
- DMARC policy enforces quarantine or rejectDMARC policy p=quarantine.39% of peers
What we saw
- Homepage checked
- https://www.skylark.co.jp/
- Homepage response
- HTTP 200
- TLS
- TLSv1.3, HTTP/2
- Certificate
- Cybertrust Japan Co., Ltd., 391-day validity, expiring 2026-12-31
- CDN or edge
- Amazon CloudFront
- DNS operators
- 2 self-run or other nameserver domains
- DMARC policy
- p=quarantine
- Homepage HTML
- 33 KB, uncompressed
- Images on homepage
- 62 (png 42, jpg 13, webp 8)
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 14
- HSTS kept for at least a year
- Certificate lifetime of 100 days or less
- CAA records limit who can issue certificates
- DNSSEC signed
- security.txt published
- X-Content-Type-Options: nosniff
- Framing restricted
- Content Security Policy present
- Referrer-Policy set
- HTTP/3 advertised
- HTML compressed
- Static files cached for 30 days or more
- Offscreen images lazy-loaded
- No render-blocking scripts in <head>
Observed 17
- HTTP requests move to HTTPS
- TLS 1.3 negotiated
- Certificate has more than 14 days left
- DMARC policy enforces quarantine or reject
- HTTP/2 negotiated
- Modern image formats in use
- robots.txt published
- XML sitemap discoverable
- Reachable over IPv6
- Canonical URL declared
- Meta description written
- Mobile viewport configured
- Structured data present
- Social preview image set
- Page language declared
- At most one redirect to the homepage
- Nameservers spread across providers
Own skylark.co.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: skylark.co.jp. This profile covers configuration only.