🌐 mozilla.biz 521 🔒 SSL Valid
Checked: just now 🔗 Visit site
✨ About this site
This is a variant domain associated with Mozilla, the technology organization widely known for developing the Firefox web browser and promoting an open internet.
📊 What the data says
This domain was registered six years ago in 2020 and currently returns an HTTP 308 status. It utilizes Cloudflare for both hosting and its technology stack, with an SSL certificate that remains valid until October 5, 2026.
HTTP Status ?A three-digit code showing if the site loaded successfully (200), redirects (301/302), or has errors (4xx/5xx).Read more →
521
SSL Expires ?When the SSL certificate expires. An expired certificate causes browser security warnings.Read more →
in 45d
Domain Expires ?When the domain registration expires. If not renewed, the domain becomes available to others.Read more →
N/A
Hosting ?The company and location where this website's server is physically located.Read more →
Unknown
Security ?Score based on key HTTP security headers: HSTS, Content-Security-Policy, and X-Frame-Options.Read more →
1/3
IP Address ?The numerical address of the server hosting this website. Reveals location, provider, and network.Read more →
104.21.91.13
Performance ?Lighthouse performance score from Google PageSpeed Insights (0–100). Measures real-world loading speed, interactivity and visual stability.
N/A
Uptime
100%
⚡ Performance ?Lighthouse performance score from Google PageSpeed Insights (0–100). Measures real-world loading speed, interactivity and visual stability.
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Performance data not available yet.

🛠️ Tech Stack ?Technologies detected on this website: CMS, frameworks, libraries, CDN, and analytics tools. 1
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🌐 CDN
Cloudflare
📸 Screenshot Processing...
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⏳

Screenshot is being captured...

🌐 DNS Records ?DNS translates domain names to IP addresses. Records control where the site, email, and services are directed.Read more →
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A (IPv4)172.67.207.76104.21.91.13
NSmitch.ns.cloudflare.combrit.ns.cloudflare.com
📋 WHOIS / RDAP ?Public registration data: who registered the domain, when, and when it expires.Read more →
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RegistrarN/A
RegisteredN/A
ExpiresN/A
Last UpdatedN/A
🔒 SSL Certificate ?Encrypts the connection between browsers and this website. Valid SSL = HTTPS works.Read more → Valid
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Subject (CN)mozilla.biz
IssuerGoogle Trust Services
Valid From2026-09-04
Valid Until2026-12-03 (45 days left)
SANs (2)mozilla.biz*.mozilla.biz
📡 HTTP Headers ?Metadata sent by the server: reveals software, caching rules, and security configuration.Read more →
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Status521
Servercloudflare
Content-Typetext/plain; charset=UTF-8
Final URLhttps://mozilla.biz/
x-frame-optionsSAMEORIGIN
referrer-policysame-origin
cache-controlprivate, max-age=0, no-store, no-cache, must-revalidate, post-check=0, pre-check=0
cf-raya4c79fdb2b84d6d3-IAD
Security headers ?HTTP headers that protect visitors from attacks. HSTS forces HTTPS, CSP controls resource loading, X-Frame-Options prevents clickjacking.Read more →
HSTS
Content-Security-Policy
X-Frame-Options
🏠 Hosting ?Physical infrastructure: where the server is, who operates it, and what network it belongs to.Read more →
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IP Address104.21.91.13
ProviderUnknown
OrganizationN/A
ASNN/A
LocationN/A
🛡️ Security Score D (3/7)
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Valid SSL
HSTS
CSP
X-Frame-Options
X-Content-Type
Referrer-Policy
Permissions-Policy
🗺️ Sitemap & Robots
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No robots.txt
This site has no robots.txt file, so crawlers may access everything by default.
Sitemap Not found
🔗 Social & Meta Tags Missing
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Titlemozilla.biz | 521: Web server is down
Languageen-US
📧 Mail Security ?Email authentication records (SPF & DMARC) that prevent spoofing and phishing from this domain.Read more →
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SPFNot set
DMARCNot set
🌍 Other TLDs ?Other top-level domain variants of this domain name and their availability. 17 active 5 for sale 1 available
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.com ●
.net taken
.org ●
.info Available
.io taken
.co taken
.dev ●
.app ●
.me ●
.biz current
.eu ●
.xyz ●
.fi ●
.se ●
.de ●
.uk taken
.fr ●
.nl ●
.es ●
.it ●
.us ●
.ca ●
.com.au ●
.co.uk taken
📡 Uptime Monitor
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Current Status 🟢 Server Error
HTTP Status 521
Response Time 172ms
Last Checked 2026-10-16 18:45:47.761753
Uptime (30d) 100%
🔗 Similar Sites 8
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mozilla.me 85% mozilla.xyz 74% mozilla.se 71% mozilla.us 68% moz.co.uk 64% moz.biz 62% mozilla.app 60% mozilla.org 60%

Similarity based on content analysis. More results appear as more domains are indexed.