How is github.io?

Looks fine risk 0/100

Registered 14 years ago, on no blocklists we checked, valid HTTPS, the site answered 200 in 56 ms.

Why

02050100

finecarefulhigh risk

·Nothing in the checks added risk.

Rule-based: domain age, blocklists, TLS. A heuristic, not a guarantee.

The home page, rendered by how.is in a sandboxed browser. Nothing on it is clickable here.

Site

200

56 ms · ends at pages.github.com

HTTPS

65 d

left on a Let's Encrypt certificate

Age

14 years

registered 2013-03-08

Blocklists

listings across 5 lists

Everything we looked at

DNS records4 record types

A	185.199.109.153 185.199.110.153 185.199.108.153 185.199.111.153
NS	ns-393.awsdns-49.com dns1.p05.nsone.net ns-692.awsdns-22.net dns3.p05.nsone.net ns-1622.awsdns-10.co.uk dns4.p05.nsone.net ns-1339.awsdns-39.org dns2.p05.nsone.net
TXT	v=spf1 a -all
CAA	{'type': 'CAA', 'issue': 'sectigo.com', 'critical': 0} {'type': 'CAA', 'critical': 0, 'issuewild': 'letsencrypt.org'} {'type': 'CAA', 'critical': 0, 'issuewild': 'sectigo.com'} {'type': 'CAA', 'issue': 'letsencrypt.org', 'critical': 0} {'type': 'CAA', 'issue': 'digicert.com', 'critical': 0} {'type': 'CAA', 'critical': 0, 'issuewild': 'digicert.com'}

RegistrationMarkMonitor Inc.

registrar	MarkMonitor Inc.
registered	2013-03-08
expires	2027-03-08
last changed	2026-08-12
owner	GitHub, Inc.
nameservers	ns-692.awsdns-22.net ns-1622.awsdns-10.co.uk dns1.p05.nsone.net dns2.p05.nsone.net dns3.p05.nsone.net
status	client delete prohibited client transfer prohibited client update prohibited

registered 2013-03-08expires 2027-03-08

HTTPS certificate65 days left

valid	yes
issuer	Let's Encrypt
covers	.github.com, .github.io, *.githubusercontent.com, github.com, github.io, githubusercontent.com
protocol	TLSv1.3

issued 2026-09-30expires 2026-12-29

DNSSECinsecure

Domain is not signed with DNSSEC

. → io → github.io

Email authenticationpoor

SPF	pass `v=spf1 a -all`
DMARC	none
DKIM	none of 1 common selectors

Whether mail claiming to be from this domain can be checked as genuine.

Security scoregrade C · 140/205

Basic Security

20/40missing: DNSSEC Enabled

Record Security

30/45missing: DMARC Record, DKIM Presence

Advanced Security

10/25missing: Mail Server Configuration, IPv6 Support

Domain Reputation

35/50missing: Typosquatting Check

Threat Detection

45/45missing: Domain Age Check

Blocklists0 listings · 14 lookups

SURBL MultidomainURIBL MultidomainSpamCop185.199.108.153Barracuda185.199.108.153UCEPROTECT Level 1185.199.108.153SpamCop185.199.109.153Barracuda185.199.109.153UCEPROTECT Level 1185.199.109.153SpamCop185.199.110.153Barracuda185.199.110.153UCEPROTECT Level 1185.199.110.153SpamCop185.199.111.153Barracuda185.199.111.153UCEPROTECT Level 1185.199.111.153

Green: clean. Red: listed. Grey: the list did not answer.

Ask it yourself

Agents get this as data. Bought through the API, the checks behind this page cost $0.070: profile $0.025 + trust $0.020 + screenshot $0.020 + site status $0.005.

curl "https://how.is/v1/domain/trust?domain=github.io" \ -H "Authorization: Bearer $HOWIS_KEY" # or pay per call in USDC (x402), no key: the 402 tells your agent the price curl -i "https://how.is/v1/domain/profile?domain=github.io"

MCP: add https://how.is/mcp to Claude, Codex or Cursor (one-line install) and ask for domain_trust on github.io. Reference: /llms.txt.

Watch github.io. DNS read at the source every 5 minutes; certificate, blocklists and expiry every 6 hours. You get an email only when something changes.

Watch — $1 / 30 days