HTTP 416 Range Not Satisfiable — Invalid Byte Range Request

Overview

HTTP 416 Range Not Satisfiable means the server cannot serve the requested byte range because it falls outside the actual size of the resource.

Key Details

• Occurs when the Range header specifies bytes beyond the resource's total size
• Example: requesting bytes 1000-2000 of a file that is only 500 bytes
• The response includes Content-Range header showing the actual resource size
• Can happen when resuming a download of a file that was replaced with a smaller version
• Also triggered by invalid range syntax in the Range header

Common Causes

• Requesting a byte range that exceeds the file size
• Resuming download of a file that has been modified or replaced since last request
• Malformed Range header syntax (e.g., bytes=abc-def)
• CDN serving cached file size that differs from origin

Steps

1. 1Check the Content-Range header in the response for the actual file size
2. 2Reset your download and start from byte 0 instead of resuming
3. 3Validate Range header syntax: Range: bytes=0-499 or Range: bytes=500-
4. 4Use a HEAD request first to get Content-Length before requesting ranges
5. 5Clear CDN cache if file size recently changed on origin

Tags

More in 4xx Client Error

Frequently Asked Questions