HTTP
418 I'm a Teapot
Any attempt to brew coffee with a teapot should result in this error. An April Fools' joke from 1998 that became a beloved part of HTTP culture.
When You See This Code
As an Easter egg on some websites, or when a server humorously refuses a request.
How to Fix
Use a coffee pot instead of a teapot. Or just enjoy the joke.
Specification
View RFC / Specification →Guides
Understanding HTTP Status Codes: A Complete Guide
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HTTP Redirects: 301 vs 302 vs 307 vs 308
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HTTP Caching: Cache-Control, ETags, and 304 Responses
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Choosing the Right HTTP Status Codes for REST APIs
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gRPC Status Codes: A Practical Guide
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Debugging Timeout Errors: 408 and 504
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401 Unauthorized vs 403 Forbidden: When to Use Each
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Essential HTTP Security Headers
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Complete Guide to HTTP Methods: GET, POST, PUT, PATCH, DELETE
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Essential HTTP Headers Every Developer Should Know
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HTTP/2 vs HTTP/3: What Changed and Why
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How to Implement and Handle Rate Limiting (429)
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API Versioning Strategies: URL, Header, and Query Param
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Designing Consistent API Error Responses
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Debugging 503 Service Unavailable Errors in Production
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TLS/SSL Certificate Troubleshooting Guide
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OAuth 2.0 Flows Explained: Authorization Code, Client Credentials, PKCE
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JSON Web Tokens: Structure, Signing, and Common Pitfalls
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API Keys vs OAuth vs JWT: Choosing the Right Auth Method
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