Website readiness profile · Snapshot 23 October 2026
transilien.com
transilien.com's public homepage, certificate and DNS checked against 31 practices and compared with 203 Trains & Public Transport sites.
- Readiness index
- 79/100
- Ahead of
- 94%
- Practices observed
- 21/30
- Popularity band
- Top 50K
Trains & Public Transport median 60
of measured Trains & Public Transport sites
1 of 31 could not be measured
Chrome UX Report top-sites list
Readiness by lane
Green: transilien.com. Thin bar: Trains & Public Transport peer median.
Enable
79/100
Peers 73
Harden
86/100
Peers 57
Accelerate
68/100
Peers 53
Recover
0/100
Peers 15
Priority fixes for transilien.com
Ordered by impact and by how common each practice is among peers.
Priority 1 · Accelerate
Modern image formats in use
Observed: The homepage had 9 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 Cloudflare: Cloudflare Polish can convert images to WebP.
28% of Trains & Public Transport 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 · Accelerate
No render-blocking scripts in <head>
Observed: The homepage <head> loaded 2 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.
43% of Trains & Public Transport peers do this.
Guide: Control Third-Party Scripts Before They Control Your Page
Priority 3 · 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.
On Drupal: The Security Kit module includes CSP settings.
34% of Trains & Public Transport peers do this.
Guide: Payment Security and PCI DSS: What Website Owners Need to Know
Priority 4 · 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.
54% of Trains & Public Transport peers do this.
What transilien.com already does well
Practices fewer than half of Trains & Public Transport peers use.
- CAA records limit who can issue certificatesCAA limits issuance to amazon.com, digicert.com, letsencrypt.org and others.8.9% of peers
- security.txt publishedsecurity.txt with a contact found.9.5% of peers
- HTTP/3 advertisedHTTP/3 advertised.28% of peers
What we saw
- Homepage checked
- https://www.transilien.com/
- Homepage response
- HTTP 200
- TLS
- TLSv1.3, HTTP/2
- Certificate
- Google Trust Services, 90-day validity, expiring 2027-01-13
- CDN or edge
- Cloudflare
- Platform or framework
- Drupal
- DNS operators
- Amazon Route 53
- HSTS
- max-age 365 days, includeSubDomains
- DMARC policy
- p=reject
- Homepage HTML
- 160 KB, br
- Images on homepage
- 9 (svg 5, png 3, jpg 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
Not observed 9
Observed 21
- HTTP requests move to HTTPS
- HSTS kept for at least a year
- TLS 1.3 negotiated
- Certificate has more than 14 days left
- Certificate lifetime of 100 days or less
- CAA records limit who can issue certificates
- security.txt published
- DMARC policy enforces quarantine or reject
- X-Content-Type-Options: nosniff
- Framing restricted
- HTTP/2 negotiated
- HTTP/3 advertised
- HTML compressed
- Offscreen images lazy-loaded
- robots.txt published
- XML sitemap discoverable
- Canonical URL declared
- Meta description written
- Mobile viewport configured
- Page language declared
- At most one redirect to the homepage
Not measured 1
- Static files cached for 30 days or more
Own transilien.com?
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: transilien.com. This profile covers configuration only.