hmhco.com

Readiness by lane

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

Priority fixes for hmhco.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 183 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.

   On Amazon CloudFront: Attach a response headers policy with Strict-Transport-Security to each distribution.

   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 · Accelerate

   Static files cached for 30 days or more

   Observed: A same-site stylesheet or script was cacheable for 0 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.

   45% of Education & Online Learning peers do this.

   Guide: Browser Caching Guide for Website Owners

3. Priority 3 · Accelerate

   Modern image formats in use

   Observed: The homepage had 26 images and none used WebP or AVIF.

   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.

   32% of Education & Online Learning peers do this.

   Guide: AVIF, WebP, JPEG, and PNG: Choose the Right Image Format

4. Priority 4 · Harden

   Framing restricted

   Observed: The homepage did not send frame-ancestors or X-Frame-Options, so other sites may frame it.

   What to do: Send Content-Security-Policy: frame-ancestors 'self' (or a list of trusted origins). X-Frame-Options: SAMEORIGIN covers older browsers.

   On Amazon CloudFront: Set frame options in a response headers policy.

   49% of Education & Online Learning peers do this.

   Guide: A Practical Website Health Check for Owners

What hmhco.com already does well

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

• DMARC policy enforces quarantine or rejectDMARC policy p=quarantine.36% of peers
• Structured data presentJSON-LD structured data found.41% of peers
• No render-blocking scripts in <head>Head scripts load without blocking.42% of peers

What we saw

Homepage checked

https://www.hmhco.com/

Homepage response

HTTP 200

TLS

TLSv1.3, HTTP/2

Certificate

GlobalSign, 90-day validity, expiring 2027-01-11

CDN or edge

Amazon CloudFront, Imperva

DNS operators

Amazon Route 53

HSTS

max-age 183 days, preload

DMARC policy

p=quarantine

Homepage HTML

503 KB, gzip

Images on homepage

26 (png 16, svg 7, jpg 3)

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

• dlt-elearning.com65
• eduki.com65
• geopop.it65
• hsslive.guru65
• icsi.edu65

Education & Online Learning readiness benchmark