X-Amz-Cf-Pop
The HTTP X-Amz-Cf-Pop response header is an unofficial, AWS-specific header identifying the Amazon CloudFront edge location serving the request.
Note
The "X-" naming convention for HTTP headers, "X" referring to "experimental", has been deprecated and needs to be transitioned to the formal naming convention for HTTP headers.
Usage
CloudFront operates a global network of edge locations, also known as Points of Presence (PoPs). When a request is processed, CloudFront includes the X-Amz-Cf-Pop header in the response to indicate which specific edge location handled the request.
The value follows a naming convention based on IATA airport codes. Each code maps to a nearby geographic location, making the header a straightforward way to determine where content was served from. This is useful for verifying CDN routing behavior, diagnosing latency, and confirming requests reach the expected regional cache.
This header is added automatically by CloudFront and is not removable using response header policies.
Values
Edge location code
The value consists of a three-letter IATA airport
code followed by a numeric identifier and a cache
tier suffix. The airport code represents the
nearest major airport to the edge location. The
numeric portion distinguishes between multiple
facilities in the same region. The suffix (such as
-P1, -P2, or -C1) indicates the cache tier
within the facility. AWS uses both -P and -C
suffix patterns across its edge network.
Example
The value starts with an IATA airport code
identifying the nearest major airport to the edge
facility. JFK refers to a data center near John
F. Kennedy International Airport in New York. The
number 52 distinguishes between multiple
facilities in the New York region, and P2
identifies the cache tier within the facility.
X-Amz-Cf-Pop: JFK52-P2
SFO refers to a facility near San Francisco
International Airport. A different facility number
and tier suffix indicate a separate cache node in
the same region.
X-Amz-Cf-Pop: SFO5-P1
HIO refers to a facility near Portland Hillsboro
Airport in Oregon. Comparing these codes across
requests helps verify whether traffic reaches the
expected geographic region.
X-Amz-Cf-Pop: HIO52-P4
Takeaway
The X-Amz-Cf-Pop header reveals which CloudFront edge location served a request, expressed as an IATA-based location code useful for verifying CDN routing and diagnosing regional performance.