deeplearningbook.org

.org crawl

First seen 2026-04-13 · Last seen 2026-05-07 · ok HTTP/1.1 200 1068 ms crawled 2026-05-06

US · 192.30.252.153 · AS36459 GitHub, Inc.

Reputation 62/100 wrong cert weak security headers no dmarc policy

Classifying

HTML metadata

Title: Deep Learning

Technology

CDN: Fastly
Server: GitHub.com

Social

Registration

Registrar

NameCheap, Inc.

Created

2015-12-25

Expires

2026-12-25 220 days left

Updated

2025-11-30

Name servers

dns1.registrar-servers.com
dns2.registrar-servers.com

DNS records live

NS

dns1.registrar-servers.com
dns2.registrar-servers.com

MX

1 aspmx.l.google.com
10 alt3.aspmx.l.google.com
10 alt4.aspmx.l.google.com
5 alt1.aspmx.l.google.com
5 alt2.aspmx.l.google.com

TXT

google-site-verification=gfXF_Vd9XJh1qq3C_iwiW3N-QGM_jgzRDbVIxhhzCbg

Email authentication partial

SPF: not published
DMARC: not published
DKIM: no key found at common selectors

Certificate (current) wrong cert

R12

from 2026-04-07 to 2026-07-06

Expires in 48 days

Full certificate history on crt.sh ↗

HTTP security headers

Header hygiene 30/100 Checked live page: https://www.deeplearningbook.org

findings

missing HSTS
missing Content Security Policy
missing frame protection
missing content type protection
missing Referrer Policy
missing Permissions Policy