102 Processing

The HTTP 102 Processing informational response status code tells the client a significant delay will occur before the final HTTP response is sent. This prevents the client from timing out too early.

Table of Contents

Usage

When a server sends the 102 Processing status code, the client maintains the HTTP connection and waits for the final response to arrive. The server must eventually return the final response, or a genuine timeout occurs.

The 102 Processing status code is no longer part of the HTTP specifications, though servers still use the code in practice. A well-implemented HTTP client ignores unrecognized informational status messages, so this response does not negatively affect clients without explicit support.

Note

Multiple 102 Processing status updates are sent in advance of the final HTTP response.

Example

The client requests a sample.pdf file, and the server returns a status code indicating processing takes longer than usual. After a short wait, the server sends another processing update. After another delay, the server sends the final response.

Request

GET /sample.pdf HTTP/1.1
Host: www.example.re

Response

HTTP/1.1 102 Processing

<there is a short pause in the transmission>

HTTP/1.1 102 Processing

<there is a short pause in the transmission>

HTTP/1.1 200 OK
Content-Type: application/pdf
Content-Length: 10000

<message body will follow>

Code references

.NET

HttpStatusCode.Processing

Rust

http::StatusCode::PROCESSING

Rails

:processing

Go

http.StatusProcessing

Symfony

Response::HTTP_PROCESSING

Python3.5+

http.HTTPStatus.PROCESSING

Apache HttpComponents Core

org.apache.hc.core5.http.HttpStatus.SC_PROCESSING

Angular

@angular/common/http/HttpStatusCode.Processing

Takeaway

The 102 Processing informational response was designed to prevent client timeouts during long-running requests, but it is no longer part of the HTTP specifications and is considered deprecated.

See also

Last updated: March 9, 2026