Location
United States
Country level only
Domain
heade.rs
Served through Cloudflare's network, which answers from the location nearest each visitor.
Still looking this up. This tab fills in as the answers arrive.
Network Every network on the internet has an autonomous system number (ASN). This is the one that announces this address.
AS13335Cloudflare
Cloudflare, Inc.
BGP prefixPrefix The block of addresses this IP is announced in to the rest of the internet. RPKI valid means the block's owner signed off on the network announcing it.
RPKI valid104.21.80.0/20
Seen by 3,467 peers
Latency Round trip for an HTTPS request from your browser to the site and back, including the server's reply time.
Live— ms
Measuring from your browser…
At a glance
Route
Finding a probe near you…
Networks crossed
Each network is an autonomous system (AS). Your traffic is handed from one to the next where they connect, following
the routes BGP advertises.
- AS14618Amazon Data Services Northern Virginia
- AS13335Cloudflare
Tracing from a probe near you with Globalping. Hop locations that its round-trip times rule out are left off the map.
Partly protected
There's no DMARC policy, so each receiver decides for itself what to do with mail that fails heade.rs's SPF check.
- Receives mail
- Cloudflare Email Routing
- Mail servers
- route3.mx.cloudflare.netroute1.mx.cloudflare.netroute2.mx.cloudflare.net
- SPFLists the servers allowed to send mail for the domain. Receivers check it against the sending server.
- Soft-fails everything else1 of 10 DNS lookups · includes _spf.mx.cloudflare.net
- DMARCTells receivers what to do with mail that fails SPF and DKIM: nothing (none), spam folder (quarantine) or reject.
- Missing
- MTA-STSRequires other mail servers to use encrypted connections (TLS) when delivering to this domain.
- Not published
- TLS reportsAsks other mail servers to report failed encrypted deliveries (TLS-RPT).
- Not requested
- BIMIA brand logo that some mail apps show next to authenticated mail from the domain.
- Not published
DNS records
TypeNameValueTTL
Aheade.rs104.21.81.985 min
Aheade.rs172.67.189.175 min
AAAAheade.rs2606:4700:3034::ac43:bd115 min
AAAAheade.rs2606:4700:3031::6815:51625 min
NSheade.rsandy.ns.cloudflare.com1 day
NSheade.rssue.ns.cloudflare.com1 day
MXheade.rs100 route2.mx.cloudflare.net5 min
MXheade.rs3 route3.mx.cloudflare.net5 min
MXheade.rs66 route1.mx.cloudflare.net5 min
TXTheade.rs"google-site-verification=A3W7bEXWVh1OdnVSWNB2NyHJbIZLGUc3OzFNDlIiFto"1 min
TXTheade.rs"v=MCPv1; k=ed25519; p=oHBCGaZdyErRDWIQqyB7wMsVqQ3n2aqTQ3JdQ7yz6ZM="1 min
TXTheade.rs"v=spf1 include:_spf.mx.cloudflare.net ~all"1 min
HTTPSheade.rs1 . alpn=h3,h2 ipv4hint=104.21.81.98,172.67.189.17 ech=AEX+DQBBiwAgACDx7lbcZ+vH88L9LsKI4dnBW3D1vBxTvtaUjwcXjlNyMwAEAAEAAQASY2xvdWRmbGFyZS1lY2guY29tAAA= ipv6hint=2606:4700:3031::6815:5162,2606:4700:3034::ac43:bd115 min
Website
Page
heade.rs · Look up any domain or IP address
Look up any domain or IP address: where it's hosted, which networks carry your traffic there, how fast it answers, and who registered it.
- Language
- English
- Theme color
- #fafafa
Built with
- CloudFrom the provider's published address ranges.
- Cloudflare
- CDN
- Cloudflarecf-ray header
- Framework
- Astropage markup
HTTPS
Certificate
Valid- Issuer
- SSL.com
- Issuing CA
- Cloudflare TLS Issuing ECC CA 4
- Covers
- *.heade.rs, heade.rs
- Also validOther unexpired certificates for this name, found in Certificate Transparency logs.
- 5 more certificates
Sep 26, 202671 days leftDec 24, 2026
From Certificate Transparency logs, via Cert Spotter.
Security
B- HSTSStrict-Transport-Security makes browsers refuse plain HTTP to this site. Preloaded sites are HTTPS-only even on a first visit.
- 2 years · with subdomains
- HTTP → HTTPSWhether the plain http:// address redirects visitors to the secure one.
- Doesn't redirect
- HTTP/3The newest HTTP, over QUIC. Announced in the alt-svc header or the domain's HTTPS DNS record.
- Available
- Encrypted helloEncrypted Client Hello (ECH) hides which site you're visiting from anyone watching the connection.
- Supported
- CAADNS records naming the only certificate authorities allowed to issue certificates for the domain.
- Any CA may issue
- security.txtA standard file (RFC 9116) telling security researchers how to report vulnerabilities.
- Not published
Security headers 5 of 7
- HSTSpresent
- CSPmissing
- Framingpresent
- No sniffingpresent
- Referrerpresent
- Permissionspresent
- Isolationmissing
Response
200 OK134 ms from EWRDNS lookup10 ms
200 heade.rs134 ms
DNSConnect (TCP + TLS)Waiting for the replyFrom Cloudflare's EWR data center
Response headers
- cache-control
- public, max-age=60
- cf-ray
- a4b04950bbdc8abe-EWR
- connection
- close
- content-type
- text/html
- date
- Thu, 15 Oct 2026 16:44:04 GMT
- nel
- {"report_to":"cf-nel","success_fraction":0.0,"max_age":604800}
- permissions-policy
- camera=(), microphone=(), geolocation=(), browsing-topics=()
- referrer-policy
- strict-origin-when-cross-origin
- report-to
{"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=5yNpbT43q6wycgRYCpLsx3tgGnaQ7LjE3O84jyQ8SlV2Jsxt%2B5F%2BbI%2FCLSFBSmuHQs6ulrqmB8lAat2QWs8WGvX07KjuxmiuwjSpOigVTr7pY6eqZBI3sukWrWegvGosEKj9jwMJ0… Show all
{"group":"cf-nel","max_age":604800,"endpoints":[{"url":"https://a.nel.cloudflare.com/report/v4?s=5yNpbT43q6wycgRYCpLsx3tgGnaQ7LjE3O84jyQ8SlV2Jsxt%2B5F%2BbI%2FCLSFBSmuHQs6ulrqmB8lAat2QWs8WGvX07KjuxmiuwjSpOigVTr7pY6eqZBI3sukWrWegvGosEKj9jwMJ0g%3D%3D"}]}- server
- cloudflare
- strict-transport-security
- max-age=63072000; includeSubDomains
- transfer-encoding
- chunked
- vary
- Accept, User-Agent
- x-content-type-options
- nosniff
- x-frame-options
- DENY
Tech stack
Built with Each entry says what gave it away: a response header, a cookie's name, an asset's path or file name, or markup the tool leaves in the page. Versions are checked against endoflife.date's support schedules and, for JavaScript packages, OSV's vulnerability database, which carries GitHub's security advisories.
CDN & edge
- Cloudflare
cf-ray header
Framework
- Astro
page markup
Fonts
- Geist
self-hosted font
- Geist Mono
self-hosted font
How it's made
- RenderingPrerendered pages are built ahead of time and served as files. Pages rendered on each request are built by server code for every visitor. Pages drawn in the browser arrive nearly empty and depend on JavaScript, which most AI crawlers don't run. Islands are interactive parts in otherwise static HTML.
- Complete HTML224 words before any script runs
- Cache-Control
- public, max-age=60
- HTML
- 80.3 KB
- Scripts
- 3 files · 9 inline1 from other sites · 2 modules
- Render-blockingPlain scripts in the page's head, without async, defer or type=module. The browser shows nothing until each one has downloaded and run.
- 1 script
Code from other sites Scripts a page loads from another domain run with the same power as its own code: they can read what visitors type and change the page. heade.rs checks what the HTML loads, not what tag managers add once they run.
- Tag manager
- Google Tag Manager
- Integrity checksSubresource Integrity: the script tag carries a hash of the file, so the browser refuses it if the other site changes it. Analytics and tag manager scripts change by design and can't carry one; pinned library files can.
- 0 of 1 script
Details
Network
- IPv4
- 104.21.81.98
- ASNThe autonomous system number of the network that announces this address.
- AS13335
- Operator
- Cloudflare, Inc.
- CDNFrom the provider's own published list of its address ranges.
- Cloudflare
- PrefixThe block of addresses announced over BGP that contains this address.
- 104.21.80.0/20
- RPKIWhether a signed record (ROA) authorizes this network to announce this prefix.
- Valid
- VisibilityHow many bgp.tools peers carry this announcement.
- 3,467 peers
- Type
- Content
- Registry
- ARIN
Location
Country level- Country
- United States
- Continent
- North America
Registration
WHOIS- Registrar
- Webglobe d.o.o.
- Registered
- Sep 25, 202620 days ago
- Expires
- Sep 25, 2027in 11 months
- Updated
- Sep 25, 2026
- StatusRegistry flags on the domain, such as locks that stop unauthorized transfers or changes.
- ActiveclientUpdateProhibited
- DNSSECDNSSEC signs DNS answers so they can't be forged on the way to you.
- Unsigned
- Name servers
- andy.ns.cloudflare.comsue.ns.cloudflare.com
- Registrant
- Individual
Sep 25, 2026346 days leftSep 25, 2027
AI & agents
Open to AI crawlers
robots.txt lets every AI crawler in. Agents that ask for Markdown get 2.6 KB instead of 80.3 KB of HTML, and it offers an MCP server, an API catalog, 1 agent skill and in-page tools.
Crawlers
Allows allTrainingSearchOn request
They visit a page when someone asks an assistant about it. ChatGPT's, Perplexity's, Meta's and Amazon's treat robots.txt as advisory;
Anthropic's and Mistral's follow it.
OpenAIGPTBotallowedOAI-SearchBotallowedChatGPT-Userallowed
AnthropicClaudeBotallowedClaude-SearchBotallowedClaude-Userallowed
GoogleGoogle-ExtendedallowedGooglebotallowed—
Microsoft—bingbotallowed—
AppleApplebot-ExtendedallowedApplebotallowed—
Perplexity—PerplexityBotallowedPerplexity-Userallowed
MetaMeta-ExternalAgentallowedMeta-WebIndexerallowedMeta-ExternalFetcherallowed
AmazonAmazonbotallowedAmzn-SearchBotallowedAmzn-Userallowed
MistralMistralAI-TrainingallowedMistralAI-IndexallowedMistralAI-Userallowed
OthersCCBotallowedBytespiderallowedDuckAssistBotallowed
- Can cite itThe AI products that can use the site in their answers: each answers from one crawler (OAI-SearchBot for ChatGPT search, Googlebot for AI Overviews, bingbot for Copilot), and robots directives on the front page, like noindex, nosnippet and noarchive, keep some out.
- ChatGPT searchClaudePerplexityAI OverviewsGeminiCopilotMeta AISiri
It's on Cloudflare, which can also block AI crawlers at its edge whatever robots.txt says.
Reading
- Without JavaScriptText on the front page before any scripts run: what GPTBot, ClaudeBot, PerplexityBot and most agents read. Google, Bing and Apple's crawlers run scripts.
- 224 words
- MarkdownAgents like Claude Code, Cursor and OpenCode ask for Markdown in their Accept header. It's the page without its markup, so it costs them far fewer tokens.
- On request2.6 KB, 31× smaller
- llms.txtA Markdown file listing a site's key pages for AI tools. Coding agents read it; search crawlers mostly don't.
- 17 links in 3 sections
- Structured dataschema.org JSON-LD in the page: facts about the site in a form machines read directly.
- WebSite, WebApplication
Tools Ways an AI agent can do things on the site, not just read it: an MCP server that apps like Claude, ChatGPT and Cursor connect to, an API catalog, packaged agent skills, a shopping profile (UCP), or tools the page offers AI in the browser (WebMCP). heade.rs looks in the official MCP Registry and the files the site publishes under /.well-known/.
- MCP serverModel Context Protocol: a server that AI apps like Claude, ChatGPT and Cursor connect to so they can use a service's tools. Servers in the official MCP Registry are published under the domain's own name, which the registry checked. A server card, which the site's AI Catalog points to, says which MCP revisions the server speaks; 2026-07-28 is the first stateless one.
- heade.rsheade.rsMCP 2026-07-28 Registry
- APIsAn API catalog (RFC 9727, at /.well-known/api-catalog) lists a site's APIs and links to their machine-readable descriptions, usually OpenAPI.
- 1 in its API catalogheade.rs · OpenAPI
- Agent skillsInstructions and scripts packaged for AI agents (SKILL.md), listed in an index at /.well-known/agent-skills/index.json or in the site's AI Catalog. Tools like Vercel's skills CLI install them.
- 1 skillDiscovery v0.2.0
- In-page toolsWebMCP: tools a page registers so AI agents in the browser, like ChatGPT's, can call them instead of clicking through the page. Only tools declared in the HTML or inline scripts can be seen here.
- lookup
- AI catalogAn index at /.well-known/ai-catalog.json of a site's MCP servers, agents and skills, for agents to find them.
- 2 entries