Why Websites Return 502 Errors
A practical explanation of 502 bad gateway errors and where to start troubleshooting.
What a 502 means
A 502 Bad Gateway error usually means one server received an invalid response from another server it depends on. The browser reached something, but the chain behind it failed.
Common causes
Causes can include an upstream app crash, overloaded service, bad deployment, proxy configuration issue, DNS problem, or temporary network failure.
What to check first
Check whether the issue affects all users, one region, one browser, or one path. Then review recent deploys, service health, logs, and upstream dependencies.
Communicate clearly
In support or incident notes, include timestamp, URL, user impact, screenshots, and whether the issue is reproducible.
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Small utilities for the next step
Severity / Priority Calculator
Use it before filing a defect, during triage, or when a team needs a quick neutral starting point.
Incident Timeline Builder
Use it during bug escalations, support handoffs, launch issues, or post-incident summaries.
Timestamp Converter
Use it when comparing log entries, user reports, screenshots, and monitoring events.
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