HTTP 100 Continue — What It Means

HTTP 100 Continue tells the client to continue sending the request body. The server has received the headers. This guide covers everything you need to know about this topic, including common causes, step-by-step solutions, and answers to frequently asked questions.

Here are the key things to understand: Status: 100 Continue. Category: 1xx Informational. The server received request headers. Client should continue sending the body. Understanding these fundamentals will help you diagnose and resolve this issue more effectively.

The most common reasons this occurs include: Client sent Expect: 100-continue header. Server acknowledges it can handle the request. Used for large POST/PUT requests. Prevents sending large body to rejecting server. Identifying the root cause is the first step toward finding the right solution.

To resolve this, follow these recommended steps: Usually handled automatically by HTTP clients. No action needed — this is normal behavior. Check if large uploads are timing out. Verify server supports Expect header. If these steps do not resolve the issue, consider consulting additional resources or a qualified professional.

This article is part of our HTTP Status Codes collection on Error Codes Wiki. We provide comprehensive, up-to-date information to help you find solutions quickly.