What does the 506 Variant Also Negotiates HTTP status code mean?

The 506 Variant Also Negotiates status code indicates that the server has a configuration error related to transparent content negotiation. It means that the resource identified by the request has a variant that itself points to the same resource, creating a circular reference that prevents the server from choosing a response.

How do I fix a 506 Variant Also Negotiates error?

Check your server's content negotiation configuration. Look for circular references in variant mappings (e.g., in .htaccess, Apache's mod_negotiation, or other negotiation settings). Simplify the negotiation rules or explicitly define the desired response without circular dependencies.

506 Server Error 📋

506 Variant Also Negotiates: A Circular Content Negotiation

Last updated: June 28, 2026 • 4 min read

✦ The Golden Answer: The 506 Variant Also Negotiates status code indicates a server configuration error in transparent content negotiation (RFC 2295). It occurs when the resource has a variant that itself points back to the same resource, creating a circular reference. The server cannot resolve which representation to serve, so it returns 506. This is a rare error, usually caused by misconfigured .htaccess, mod_negotiation, or other content negotiation directives that create infinite loops.

What Is Transparent Content Negotiation?

Transparent content negotiation is a mechanism where the server selects the best representation of a resource based on client headers (e.g., Accept-Language, Accept-Encoding). The server can offer multiple variants (e.g., different languages, formats) and chooses the most appropriate one. If the negotiation rules create a loop (variant A points to variant B, which points back to variant A), the server cannot decide and returns 506.

Common Causes of 506 Errors

Cause	Example	How to Fix
Circular variant references	Variant A says "choose variant B" and variant B says "choose variant A".	Break the loop by explicitly defining the variants without mutual references.
Misconfigured .htaccess	Apache `Multiviews` or `RewriteRule` that redirects to itself.	Check rewrite rules and negotiation settings; ensure they don't create loops.
Content negotiation module errors	mod_negotiation misconfiguration.	Simplify negotiation rules or disable transparent negotiation if not needed.
Proxy or CDN interference	A proxy adds headers that trigger a loop.	Check proxy settings; ensure they don't modify negotiation headers.

Example: 506 Response

HTTP/1.1 506 Variant Also Negotiates
Content-Type: text/html

<html>
<body>
  <h1>506 Variant Also Negotiates</h1>
  <p>The server encountered a circular reference in content negotiation.</p>
</body>
</html>

How to Fix 506 Errors

Check Apache configuration: If you're using Apache's Multiviews or RewriteRule, look for loops. Simplify the negotiation rules.
Disable transparent negotiation: If you don't need it, turn it off. In Apache, you can remove Options +MultiViews or set MultiviewsMatch Any carefully.
Use explicit redirects: Instead of relying on negotiation, use explicit 301/302 redirects to the correct variant.
Check for proxy loops: If you have a reverse proxy, ensure it doesn't add headers that cause the server to renegotiate infinitely.

Preventing 506 Errors

Test negotiation rules thoroughly – simulate requests with different headers to ensure no loops.
Monitor logs – watch for negotiation errors in server logs.
Simplify configuration – avoid complex negotiation hierarchies.

Frequently Asked Questions

Is 506 a client error or a server error?

It's a server error (5xx) because the server's configuration is faulty. The client's request is valid, but the server cannot process it due to its own misconfiguration.

Can I see 506 in the wild?

Very rarely. It mostly occurs in poorly configured Apache servers with mod_negotiation enabled. Most modern sites avoid transparent negotiation in favor of explicit redirects or server-side language detection.

What is the difference between 506 and 500?

506 is a specific error for negotiation loops. 500 is a generic catch-all for any other internal error.

Related Codes: 500 Internal Server Error 501 Not Implemented 406 Not Acceptable 300 Multiple Choices