nta.go.jp

Readiness by lane

Green: nta.go.jp. Thin bar: Government Services peer median.

Priority fixes for nta.go.jp

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

1. Priority 1 · Accelerate

   HTML compressed

   Observed: The homepage HTML (73 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.

   74% of Government Services 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

2. 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.

   51% of Government Services peers do this.

   Guide: HTTPS and TLS Guide for Website Owners

3. Priority 3 · Accelerate

   Static files cached for 30 days or more

   Observed: A same-site stylesheet or script was cacheable for no max-age, 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.

   30% of Government Services peers do this.

   Guide: Browser Caching Guide for Website Owners

4. Priority 4 · Accelerate

   No render-blocking scripts in <head>

   Observed: The homepage <head> loaded 6 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.

   39% of Government Services peers do this.

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

What nta.go.jp already does well

Practices fewer than half of Government Services peers use.

• DNSSEC signedDNSSEC delegation (DS record) present.19% of peers
• Reachable over IPv6IPv6 address published.27% of peers
• XML sitemap discoverableSitemap found.42% of peers

What we saw

Homepage checked

https://www.nta.go.jp/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

GlobalSign, 199-day validity, expiring 2027-04-17

CDN or edge

Amazon CloudFront

DNS operators

Azure DNS

DMARC policy

p=quarantine

Homepage HTML

73 KB, uncompressed

Images on homepage

19 (png 15, jpg 3, gif 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 Government Services sites

• hec.gov.pk50
• nctb.gov.bd50
• ncts.ie50
• portaldasfinancas.gov.pt50
• registrodeempresasysociedades.cl50

Government Services readiness benchmark