Location
United States
Country level only
Domain
docker.com
Hosted by Fastly in the United States. Only the country is known, which is common for anycast and CDN addresses.
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.
AS54113Fastly
Fastly, 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 valid23.185.0.0/24
Seen by 3,197 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.
- AS16509Anthropic, PBC
- AS54113Fastly
Tracing from a probe near you with Globalping. Hop locations that its round-trip times rule out are left off the map.
Protected from spoofing
Mail that fails its checks is sent to spam under docker.com's DMARC policy, so forged mail doesn't reach inboxes.
- Receives mail
- Google Workspace
- Mail servers
- aspmx.l.google.comalt1.aspmx.l.google.comalt2.aspmx.l.google.com+2 more
- SPFLists the servers allowed to send mail for the domain. Receivers check it against the sending server.
- Rejects everything else6 of 10 DNS lookups · includes _spf.google.com, spf.tipalti.com…
- DMARCTells receivers what to do with mail that fails SPF and DKIM: nothing (none), spam folder (quarantine) or reject.
- Quarantinesends reports
- 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
Adocker.com23.185.0.44 min
AAAAdocker.com2620:12a:8001::45 min
AAAAdocker.com2620:12a:8000::45 min
NSdocker.comns-1289.awsdns-33.org2 days
NSdocker.comns-1981.awsdns-55.co.uk2 days
NSdocker.comns-207.awsdns-25.com2 days
NSdocker.comns-568.awsdns-07.net2 days
MXdocker.com1 aspmx.l.google.com1 hr
MXdocker.com10 alt3.aspmx.l.google.com1 hr
MXdocker.com10 alt4.aspmx.l.google.com1 hr
MXdocker.com5 alt1.aspmx.l.google.com1 hr
MXdocker.com5 alt2.aspmx.l.google.com1 hr
TXTdocker.com"MS=ms42223923"5 min
TXTdocker.com"MS=ms98031138"5 min
TXTdocker.com"adobe-idp-site-verification=a8d1a71d0cba44c2521bcb451d9dc708ee20d93c7b5b04791f699d128bbe6ec2"5 min
TXTdocker.com"airtable-verification=7f122efe7db6b16848108e469042c39c"5 min
TXTdocker.com"anthropic-domain-verification-p1ks1q=BmUzJzzDzqNXVWLXmZVoEvTr3"5 min
TXTdocker.com"apple-domain-verification=S580UenDqcwy2I1X"5 min
TXTdocker.com"astro-domain-verification=cljrj1fgz00hm01lvtaq65gnn"5 min
TXTdocker.com"atlassian-domain-verification=I1f5bgOm9sPUEcK/2JTD6weNlWt+Wwsyo5dwvJe1fGjf9V+x3kyqxZRrl9z7ILEK"5 min
TXTdocker.com"cursor-domain-verification-pkwbtp=KD6kIrkeudCadzeviiVJgEWnd"5 min
TXTdocker.com"d0vcwvtyam"5 min
TXTdocker.com"detectify-verification=87a64c3bf3301354588d90672bd1b74e"5 min
TXTdocker.com"docker-verification=4b72827b-32c1-4fe6-a843-2256c0df8a31"5 min
TXTdocker.com"docusign=aeb25cd4-f743-4efc-b6fb-b8bc5dd1d0e8"5 min
TXTdocker.com"google-site-verification=4PyKLfy_lowkc_qcu-byUkmF1kxAUT7tfho7ZiP353s"5 min
TXTdocker.com"google-site-verification=5e33xBJIwW1XU49IqmIYtN7yi2Iq0GNnWwN4ujn4G_M"5 min
TXTdocker.com"google-site-verification=CFmV0geNs1hCxK0mBEpjWaDoNwBIiDxIRjTvt3YGRDM"5 min
TXTdocker.com"google-site-verification=GjEZ_3KyjpDbmRzGdMUtqMeuXdh7HCSc8uRsPGYL-I0"5 min
TXTdocker.com"google-site-verification=Nyiwo5q4kkaD5V-sEiXsW74HXyVRtKVyxYFfZuFLG7M"5 min
TXTdocker.com"google-site-verification=VbuWA5NflxQMko2x9BJFIPVYrbuxHQll4UP4gZ4Fm08"5 min
TXTdocker.com"google-site-verification=i6hYWAXRYCtHNnyiQAYXiy_4StkAMJQiNCfH-3olY-I"5 min
TXTdocker.com"google-site-verification=rCKOZlVmB_xuu9DiT-urSmmXAEUGn5RI8PxdyCW5LJg"5 min
TXTdocker.com"jamf-site-verification=jqNgc5MzMp4UnSANweyyEQ"5 min
TXTdocker.com"miro-verification=116f0987438eb5a48c070e080a68e7d7b3087e5f"5 min
TXTdocker.com"onetrust-domain-verification=fb12882ae6344670a7b91077bd57c0f1"5 min
TXTdocker.com"openai-domain-verification=dv-tj9VEsgExQvdNl9SCOa2Awju"5 min
TXTdocker.com"opine-verification=14d8ea53-d8ae-406f-93b0-76dc879d9b46"5 min
TXTdocker.com"sinch-domain-verification=d8a66194-44cf-49c3-96ab-74325ad6e7be"5 min
TXTdocker.com"sonatype-domain-verification=OSSRH-62474"5 min
TXTdocker.com"stripe-verification=804359af3a919b4a46343227e384abdf33e10ad5bb81ea9f1d17ed4e74486ab4"5 min
TXTdocker.com"v=spf1 include:_spf.google.com include:spf.tipalti.com include:_spf.salesforce.com include:mktomail.com include:mail.zendesk.com -all"5 min
TXTdocker.com"zapier-domain-verification-challenge=c3e7ddaf-20bf-40ca-9374-1a917b16be06"5 min
TXT_dmarc.docker.com"v=DMARC1; p=quarantine; pct=100; rua=mailto:q1xwnepx@ag.dmarcian.com; ruf=mailto:q1xwnepx@fr.dmarcian.com;"5 min
CAAdocker.com0 iodef "mailto:infra+caa-iodef@docker.com"5 min
CAAdocker.com0 issue "amazon.com"5 min
CAAdocker.com0 issue "comodoca.com"5 min
CAAdocker.com0 issue "digicert.com"5 min
CAAdocker.com0 issue "letsencrypt.org"5 min
CAAdocker.com0 issue "pki.goog"5 min
CAAdocker.com0 issue "sectigo.com"5 min
HTTPS
Certificate
Valid- Issuer
- Let's Encrypt
- Issuing CA
- YR1
- Covers
- docker.com, www.docker.com
- Also validOther unexpired certificates for this name, found in Certificate Transparency logs.
- 9 more certificates
Sep 28, 202676 days leftDec 27, 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.
- 1 year
- HTTP → HTTPSWhether the plain http:// address redirects visitors to the secure one.
- Redirects
- HTTP/3The newest HTTP, over QUIC. Announced in the alt-svc header or the domain's HTTPS DNS record.
- Not announced
- CAADNS records naming the only certificate authorities allowed to issue certificates for the domain.
- Amazon, Sectigo, DigiCert, Let's Encrypt, Google Trust Services
- security.txtA standard file (RFC 9116) telling security researchers how to report vulnerabilities.
- security@docker.com
Security headers 5 of 7
- HSTSpresent
- CSPmissing
- Framingpresent
- No sniffingpresent
- Referrerpresent
- Permissionspresent
- Isolationmissing
Response
200 OK33 ms from CMH · 139.9 KBDNS lookup4 ms
301 docker.com50 ms
200 www.docker.com33 ms
DNSConnect (TCP + TLS)Waiting for the replyFrom Cloudflare's CMH data center
Response headers
- connection
- close
- content-length
- 143220
- cache-control
- public, max-age=604800
- content-encoding
- gzip
- content-type
- text/html; charset=UTF-8
- link
- <https://www.docker.com/wp-json/>; rel="https://api.w.org/"
- link
- <https://www.docker.com/wp-json/wp/v2/pages/69521>; rel="alternate"; title="JSON"; type="application/json"
- link
- <https://www.docker.com/>; rel=shortlink
- server
- nginx
- strict-transport-security
- max-age=31622400
- x-pantheon-styx-hostname
- styx-us-a-58d475665b-f4l6f
- x-styx-req-id
- 02ada4dd-c656-11f1-8544-de59df14ad40
- age
- 234
- accept-ranges
- bytes
- via
- 1.1 varnish, 1.1 varnish, 1.1 varnish, 1.1 varnish
- x-content-type-options
- nosniff
- referrer-policy
- strict-origin-when-cross-origin
- permissions-policy
- geolocation=(), microphone=(), camera=(), fullscreen=(self "https://www.youtube.com"), payment=()
- x-frame-options
- SAMEORIGIN
- x-xss-protection
- 1; mode=block
- date
- Mon, 12 Oct 2026 16:04:07 GMT
- x-served-by
- cache-chi-kmdw8640070-CHI, cache-cmh1290098-CMH, cache-cmh1290056-CMH, cache-cmh1290056-CMH
- x-cache
- HIT, HIT, MISS, MISS
- x-cache-hits
- 72, 71, 0, 0
- x-timer
- S1791821048.685619,VS0,VE10
- vary
- Accept-Encoding, X-Language-Locale, Cookie, Cookie
Details
Network
- IPv4
- 23.185.0.4
- ASNThe autonomous system number of the network that announces this address.
- AS54113
- Operator
- Fastly, Inc.
- PrefixThe block of addresses announced over BGP that contains this address.
- 23.185.0.0/24
- RPKIWhether a signed record (ROA) authorizes this network to announce this prefix.
- Valid
- VisibilityHow many bgp.tools peers carry this announcement.
- 3,197 peers
- Type
- Content
- Registry
- ARIN
Location
Country level- Country
- United States
- Continent
- North America
Registration
RDAP- PopularityCloudflare Radar's ranking of domains by how often 1.1.1.1 users look them up.
- Top 1,000
- Registrar
- Gandi SAS
- Registered
- Jan 25, 199531 years ago
- Expires
- Jan 26, 2027in 3 months
- Updated
- Jan 13, 2026
- StatusRegistry flags on the domain, such as locks that stop unauthorized transfers or changes.
- Transfer locked
- DNSSECDNSSEC signs DNS answers so they can't be forged on the way to you.
- Unsigned
- Name servers
- ns-1289.awsdns-33.orgns-1981.awsdns-55.co.ukns-207.awsdns-25.comns-568.awsdns-07.net
- Registrant
- Redacted for privacy
Jan 25, 1995106 days leftJan 26, 2027
Website
Page
Docker | Secure Sandboxes for AI Agents
Run AI agents and containers safely, anywhere. Docker gives builders trusted sandboxes, governance, and a secure supply chain for modern software.
- Language
- American English
- Generator
- WordPress 7.1.3
Built with
- Hosting
- Pantheonx-pantheon-styx-hostname header
- CDN
- Fastlyx-served-by header
- CMS
- WordPresspage markup
- Server
- nginxserver header “nginx”
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.
Hosting
- Pantheon
x-pantheon-styx-hostname header
CDN & edge
- Fastly
x-served-by header
Server
- nginx
server header “nginx”
CMS
- WordPress7.1.3Supported
generator tag “WordPress 7.1.3”
Add-ons
- Rank Math
HTML comment
Fonts
- Jost
self-hosted font
- Roboto Flex
self-hosted font
- Mali
self-hosted font
- Inter
from Google Fonts
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 HTML1,024 words before any script runs
- Edge cacheWhether a CDN or proxy answered heade.rs's request from its cache, and how long ago that copy was made (the Age header).
- Served from cacheFastly · made 4 min ago
- Cache-Control
- public, max-age=604800
- HTML
- 409.7 KB · sent gzip-compressed
- Scripts
- 46 files · 12 inline3 from other sites
- 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.
- Consent
- OneTrust
- Fonts
- Google Fonts
- 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 3 scripts
AI & agents
Open to AI crawlers
robots.txt lets every AI crawler in.
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
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.
- 1,024 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.
- Not offered
- llms.txtA Markdown file listing a site's key pages for AI tools. Coding agents read it; search crawlers mostly don't.
- Not published
- Structured dataschema.org JSON-LD in the page: facts about the site in a form machines read directly.
- Corporation, WebSite, WebPage, VideoObject
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/.
Couldn't check: the site didn't answer heade.rs's requests for its agent files.