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zermelo.nl

.nl ok HTTP/1.1 200 558 ms

First seen 2026-06-17 · Last seen 2026-06-17 · crawled 2026-06-17

IE · 34.254.7.188 · AS16509 Amazon.com, Inc.

Reputation 100/100

sector education subsector education media type homepage

HTML metadata

Title
Zermelo - Zermelo maakt beter onderwijs mogelijk
Language
nl

Contact

Technology

Server
nginx
CMS
Gatsby

Social

Registration

Registrar
Gandi
Created
1999-09-13
Updated
2024-03-01
Name servers
  • ns-621.awsdns-13.net
  • ns-1745.awsdns-26.co.uk
  • ns-507.awsdns-63.com
  • ns-1204.awsdns-22.org

DNS records live

NS
  • ns-1204.awsdns-22.org
  • ns-1745.awsdns-26.co.uk
  • ns-507.awsdns-63.com
  • ns-621.awsdns-13.net
MX
  • 10 inbound-smtp.eu-west-1.amazonaws.com
TXT
  • bw=OiynCV9cNEulLYpgZu7GBCq6V5KhpgaSiHIi/wdvgTzU
Verified for
  • Apple
  • Microsoft 365

Email authentication strong

SPF
v=spf1 include:spf.protection.outlook.com include:amazonses.com include:_spf.exactonline.nl ~all
softfail (~all)
DMARC
v=DMARC1; p=reject
policy: reject (enforced)
DKIM
  • default: v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC87dYobBeSYe8JCuSzgaiEc/RPgOxn+mIQFtkuKke5ZOES+JrlVUbZoUJmVBkzM45UFFimpiiY7xpS4EJu2e…
  • k1: k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCkO5oSw0kQv9jniq5iAF3WcYxoN6BfSujNjQNJLp0eE7NFHaQetuHiPTgZCcmalBTvFgx2W6kHAhYFcEk+Vy/tgE7aBMY…
  • smtpapi: k=rsa; t=s; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDPtW5iwpXVPiH5FzJ7Nrl8USzuY9zqqzjE0D1r04xDN6qwziDnmgcFNNfMewVKN2D1O+2J9N14hRprzByFwfQW76…
selectors probed

Certificate (current)

YR1
from 2026-06-13 to 2026-09-11
Expires in 83 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 55/100 Checked live page: https://zermelo.nl/

present
  • x-frame-options
  • x-content-type-options
  • referrer-policy
  • cross-origin-opener-policy
findings
  • missing HSTS
  • missing Content Security Policy
  • missing Permissions Policy
Header values
referrer-policy
same-origin
x-frame-options
DENY
x-content-type-options
nosniff
cross-origin-opener-policy
same-origin

Links to (1)

Linked from (1)

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