Retry-After
E200851
Retry-After is an HTTP response header that tells clients how long to wait before making another request, typically used with status codes like 429 or 503 to indicate a temporary condition.
All labels observed (2)
| Label | Occurrences |
|---|---|
| Expires (HTTP header) | 1 |
| Retry-After canonical | 1 |
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
HTTP header
ⓘ
HTTP response header field ⓘ |
| associatedWithConcept |
exponential backoff
ⓘ
graceful degradation ⓘ idempotent requests ⓘ |
| category | response control header ⓘ |
| definedIn |
RFC 7231
ⓘ
RFC 9110 ⓘ |
| direction | server-to-client ⓘ |
| discourages | immediate retry after a temporary failure ⓘ |
| effectOnClient | encourages reduced request frequency ⓘ |
| errorConditionType | temporary condition ⓘ |
| hasHeaderName | Retry-After ⓘ |
| helpsWith |
implementing polite client behavior
ⓘ
protecting servers from overload ⓘ |
| interpretedBy |
API clients
ⓘ
HTTP clients ⓘ web browsers ⓘ |
| isOptional | true ⓘ |
| mayBeIgnoredByClients | true ⓘ |
| protocol |
HTTP/1.1
ⓘ
HTTP/2 ⓘ HTTP/3 ⓘ |
| relatedHeader |
RateLimit-Reset
ⓘ
RateLimit-Reset-After ⓘ X-RateLimit-Reset ⓘ |
| scope | applies to the request that triggered the response ⓘ |
| semantics | indicates how long the client should wait before making a follow-up request ⓘ |
| semanticsDetail |
for HTTP-date value, client should not retry before the given date and time
ⓘ
for delta-seconds value, client should wait at least that many seconds before retrying ⓘ |
| statusCodeCategory |
commonly used with 4xx responses
ⓘ
commonly used with 5xx responses ⓘ |
| typicalUseCase |
API rate limit exceeded and client must delay further requests
ⓘ
server is overloaded and asks clients to wait before retrying ⓘ service temporarily down for maintenance ⓘ |
| unitForDeltaSeconds | seconds ⓘ |
| usedFor |
backoff signaling
ⓘ
rate limiting ⓘ temporary server unavailability ⓘ |
| usedWithStatusCode |
3xx redirection responses (historical / less common)
ⓘ
429 ⓘ 503 ⓘ |
| valueFormatExample |
120
ⓘ
Wed, 21 Oct 2015 07:28:00 GMT ⓘ |
| valueType |
HTTP-date
ⓘ
delta-seconds ⓘ |
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.