How to Fix 413 Request Entity Too Large Error in Nginx

The 413 Request Entity Too Large error in nginx happens when a client sends a request larger than the server allows. To fix it, increase the client_max_body_size value in your nginx configuration and reload nginx to apply the change.

Why This Happens

This error occurs because nginx limits the size of client requests to protect the server from very large uploads or attacks. If a client tries to send data bigger than the allowed size, nginx rejects it with a 413 error.

nginx

server {
    listen 80;
    server_name example.com;

    location /upload {
        # No client_max_body_size set here
    }
}

Output

413 Request Entity Too Large

The Fix

To fix this, add or increase the client_max_body_size directive in your nginx configuration. This sets the maximum allowed size for client requests. For example, to allow uploads up to 50 megabytes, set it to 50M. Then reload nginx to apply the change.

nginx

server {
    listen 80;
    server_name example.com;

    location /upload {
        client_max_body_size 50M;
    }
}

Output

Nginx reload successful; uploads up to 50MB accepted

Prevention

To avoid this error in the future, always set client_max_body_size to a value that fits your application's needs. Review your expected upload sizes and configure nginx accordingly. Use configuration management tools to keep your settings consistent and test changes in a staging environment before production.

Related Errors

Other errors related to request size include:

• 413 Payload Too Large: Similar to 413 Request Entity Too Large, used in HTTP/2.
• 504 Gateway Timeout: Can happen if large uploads take too long.
• 400 Bad Request: May occur if the request is malformed or truncated due to size limits.

Adjusting client_max_body_size and timeout settings usually helps fix these.

Key Takeaways

Increase client_max_body_size in nginx config to fix 413 errors.

Reload nginx after changing configuration to apply updates.

Set client_max_body_size based on your application's upload needs.

Test configuration changes in a safe environment before production.

Related errors often involve request size or timeout settings.