HTTP 100 Continue vs 308 Permanent Redirect
HTTP 100 (Continue) is a 1xx Informational response, while 308 (Permanent Redirect) is a 3xx Redirection response. 100 indicates that the server has received the request headers and the client should proceed to send the request body. This lets the client know it can continue with the request or abort if the headers were rejected. In contrast, 308 means that the resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed.
Description
The server has received the request headers and the client should proceed to send the request body. This lets the client know it can continue with the request or abort if the headers were rejected.
When You See It
When a client sends an Expect: 100-continue header, the server responds with 100 before the client sends the body.
How to Fix
This is an interim response — no fix needed. The client should continue sending the request body.
Description
The resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed.
When You See It
For permanent URL changes where POST requests must remain POST.
How to Fix
Update all references to the new URL. The HTTP method is preserved.
Key Differences
100 is a 1xx Informational response, while 308 is a 3xx Redirection response.
HTTP 100: The server has received the request headers and the client should proceed to send the request body. This lets the client know it can continue with the request or abort if the headers were rejected.
HTTP 308: The resource has been permanently moved. Like 301, but guarantees the HTTP method will NOT be changed.
You encounter 100 when when a client sends an Expect: 100-continue header, the server responds with 100 before the client sends the body.
You encounter 308 when for permanent URL changes where POST requests must remain POST.
When to Use Which
For 100 (Continue): This is an interim response — no fix needed. The client should continue sending the request body. For 308 (Permanent Redirect): Update all references to the new URL. The HTTP method is preserved.