HTTP Paging / Status Code Simulator
Updated Mar 6, 2026
An educational simulator that walks you through how common HTTP responses occur across a typical web stack — Client, CDN/LB, Reverse Proxy, App, and Dependency layers. Watch animated request flows, see exactly where each failure originates, and get practical troubleshooting guidance.
Covers 10 status codes (200, 301, 401, 403, 404, 429, 500, 502, 503, 504) with step-by-step animations, request/response details with headers, alerting/paging context, and a quick-reference card section. Great for SREs, support engineers, and developers learning how failures propagate through infrastructure.
Scenario
Select an HTTP status code to simulate.
Successful request — everything works.
Request Flow
Press Play or Step to begin the simulation.
Status Code Quick Reference
All status codes covered by this simulator at a glance.
The request succeeded and the server returned the requested resource.
The resource has permanently moved to a new URL. Clients should update bookmarks and links.
Authentication is required. The request lacks valid credentials or the token has expired.
The server understood the request but refuses to authorize it. You're authenticated but not allowed.
The server can't find the requested resource. The URL may be wrong or the resource was deleted.
Rate limit exceeded. Wait for the Retry-After period before sending more requests.
A generic server-side error. The server hit an unexpected condition (unhandled exception, bug).
The proxy received an invalid or no response from the upstream server. The app may be crashed.
The server is temporarily overloaded or in maintenance. Usually a capacity or deployment issue.
The proxy timed out waiting for the upstream server. A slow dependency is the most common cause.