What powers sijthoff-leiden.nl?
Last seen Sep 2026 · 34 technologies across 16 categories
Advertising
Twitter Ads
since Dec 2021
Authentication
Facebook Login
since Dec 2021
Google Sign-in
since Dec 2021
CMS
Comment systems
Databases
MySQL
since Dec 2021
Font scripts
Google Font API
since Dec 2021
Twitter Emoji (Twemoji)
since Dec 2021
JavaScript libraries
Maps
Marketing automation
MailChimp
since Dec 2021
Miscellaneous
Page builders
WordPress Block Editor
since Jul 2024
Programming languages
PHP
since Dec 2021
Web servers
Apache HTTP Server
since Feb 2023
LiteSpeed
since Dec 2021
Widgets
Twitter
since Dec 2021
WordPress plugins
Contact Form 7
since Apr 2022
GenerateBlocks
since Mar 2023
MailChimp for WordPress
since Apr 2022
SiteOrigin Page Builder
since Apr 2022
The Events Calendar
since Apr 2022
WordPress themes
AI Crawlers
Doesn't name any of the 33 AI crawlers we track in its robots.txt. Catch-all rules (User-agent: *) restrict some paths for every crawler, AI or not. Checked Sep 2026.
- robots.txt found
- llms.txt not found
- ai.txt not found
AI Crawlers
No AI crawlers blocked
Audience
- 80% phone
- 20% desktop
Netherlands
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
3.31 / 10 · ranked #1,118,401 of all domains
27 referring domains · OpenPageRank
Page
- Language: Dutch (Netherlands)
- Weight: 9.1 MB · 73 requests
- WordPress theme: generatepress (child: generatepress-child-theme) · all themes
- Structured data: Microdata
Homepage as crawled by the HTTP Archive, Oct 2026.
Infrastructure
- DNS: greenhost.nl
- Email: greenhost.nl
- Email security: SPF (soft fail), DMARC monitor only, DNSSEC signed
- SSL: Let's Encrypt, RSA 3072, expires Nov 2026
- Common Crawl link graph: rank 716,249, 2 hosts
DNS records as swept Sep 2026, certificate as seen Sep 2026. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| www.sijthoff-leiden.nl | 26 |
| sijthoff-leiden.nl | 23 |