HTTP 103 — Early Hints

Allows the server to send link headers to prefetch resources while compiling the main response.

Status CodeHTTP 103

CategoryInformational (1xx)

API Error Subtypes0 error schemas

HTTP Headers1 header

What does HTTP status code 103 mean?

The 103 Early Hints status code is primarily intended to be used with the Link header to allow the user agent to start preloading resources while the server prepares the final response payload.

When to use it in APIs

Useful in high-performance web applications or APIs returning HTML/critical assets where the browser can benefit from preloading CSS, JS, or font assets early in the connection lifecycle.

How it compares to other codes

200 OK: The final successful response. 103 is a pre-response hint sent before 200.

Specific API Error Types for 103

No specific Problem+JSON schemas have been defined for HTTP 103 on apiguide.dev yet.

Associated HTTP Headers

Link

Provides a means to serialize relationships between resources in HTTP headers, commonly used for pagination.

View reference →

Related HTTP Status Codes

HTTP 200 — OK

The request has succeeded. The response payload contains the requested resource representation.