Where Am I?

Retrieve detailed metadata about incoming requests from Cloudflare's edge network, including geographic location, data center, ASN, and timezone.

API Reference

GET /whereami

Returns the Cloudflare request.cf object containing metadata about the incoming request.

Example Request

curl "https://your-worker.workers.dev/whereami"

Success Response

The response includes whatever Cloudflare injects into request.cf for the incoming request. Common fields include:

country string

Two-letter ISO 3166-1 country code (e.g., "US", "GB")

city string

City name (e.g., "San Francisco")

region string

Region or state name (e.g., "California")

timezone string

IANA timezone identifier (e.g., "America/Los_Angeles")

colo string

Cloudflare data center IATA code (e.g., "SFO", "LHR")

asn number

Autonomous System Number of the client's ISP

{
  "country": "US",
  "city": "San Francisco",
  "region": "California",
  "timezone": "America/Los_Angeles",
  "colo": "SFO",
  "asn": 13335
}

Additional Request Metadata Fields

Depending on the request, the cf object may also include:

• latitude / longitude - Geographic coordinates
• postalCode - Postal/ZIP code
• metroCode - Metro area code
• continent - Two-letter continent code
• regionCode - ISO 3166-2 region code
• tlsVersion - TLS version used (e.g., "TLSv1.3")
• tlsCipher - TLS cipher suite
• httpProtocol - HTTP protocol version (e.g., "HTTP/2")

See the Cloudflare request.cf documentation for a complete list.

Implementation Details

• Completely stateless - no external requests
• No database or KV storage required
• Returns raw request.cf object from Cloudflare
• Works immediately after deployment

Use Cases

• Determine visitor geographic location without external APIs
• Display localized content based on country/region
• Show the nearest edge data center serving the request
• Analyze traffic patterns by ASN or location
• Build geographic routing logic

Limitations

• Returns Cloudflare request.cf metadata only; not a standalone geolocation API
• Local development returns minimal or empty cf data
• Available fields vary by request path and Cloudflare detection capabilities

Deployment

curl "https://your-worker.workers.dev/whereami"

Local Development

cd apps/experiments/whereami
npm install
npm run dev

Test locally:

curl "http://localhost:8787/whereami"

Cloudflare Features Used

• Workers - Edge compute runtime
• request.cf - Incoming request metadata including geolocation