w3schools.com

Readiness by lane

Green: w3schools.com. Thin bar: Education & Online Learning peer median.

Priority fixes for w3schools.com

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

1. Priority 1 · Harden

   HSTS kept for at least a year

   Observed: Strict-Transport-Security was sent with a max-age of 30 days, below the one-year benchmark.

   Why it matters: HSTS tells browsers to use HTTPS for your host on every later visit, which removes the window where a first HTTP request can be intercepted.

   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.

   34% of Education & Online Learning peers do this. Limit: Read from the homepage response only; other pages or regions may send different headers.

   Guide: HTTPS and TLS Guide for Website Owners

2. Priority 2 · Enable

   XML sitemap discoverable

   Observed: No sitemap was listed in robots.txt or found at /sitemap.xml.

   What to do: Generate an XML sitemap of canonical URLs, reference it in robots.txt and submit it in Google Search Console.

   65% of Education & Online Learning peers do this.

   Guide: XML Sitemap Guide: Include Only URLs You Stand Behind

3. Priority 3 · 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.

   42% of Education & Online Learning peers do this.

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

4. Priority 4 · Enable

   Canonical URL declared

   Observed: The homepage did not declare a canonical URL.

   What to do: Add a self-referencing canonical link to every indexable page, using the final https:// URL.

   62% of Education & Online Learning peers do this.

   Guide: Canonical Tags: A Decision Guide for Duplicate URLs

What w3schools.com already does well

Practices fewer than half of Education & Online Learning peers use.

• Content Security Policy presentContent-Security-Policy present.25% of peers
• Referrer-Policy setReferrer-Policy present.27% of peers
• Modern image formats in useWebP or AVIF images detected.32% of peers

What we saw

Homepage checked

https://www.w3schools.com/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

Let's Encrypt, 89-day validity, expiring 2027-01-03

DNS operators

Amazon Route 53

HSTS

max-age 30 days

DMARC policy

p=reject

Homepage HTML

364 KB, gzip

Images on homepage

28 (webp 14, png 13, svg 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 Education & Online Learning sites

• 6xclassroom.io68
• ruangguru.com69
• studenti.it69
• vajiramandravi.com69
• wayground.com69

Education & Online Learning readiness benchmark