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Published at: May 13, 2025Last Updated at: 5/13/2025, 2:53:43 PM
GitHub imposes rate limits on requests made to its APIs, Git operations, and other services. These limits restrict the number of actions or requests an individual user or application can perform within a specific time frame. The primary purpose is to prevent abuse, ensure the stability and performance of the platform for all users, and manage resource consumption effectively.
GitHub implements various rate limits depending on the service being accessed. The most commonly encountered limits relate to API usage:
For the core REST API, rate limits are typically measured in requests per hour. The limit varies significantly based on whether the request is authenticated or unauthenticated. Other limits, like search or secondary limits, might be measured over shorter durations or based on complexity.
A fundamental distinction in GitHub rate limits is between authenticated and unauthenticated requests:
Authenticated requests are the standard and recommended way to interact with GitHub's APIs for any significant usage.
Applications and users can check their current rate limit status for the REST API by making a GET request to /rate_limit
. This endpoint returns information about the various rate limits that apply, including:
X-RateLimit-Limit
: The maximum number of requests permitted in the current time window.X-RateLimit-Remaining
: The number of requests remaining in the current time window.X-RateLimit-Reset
: The Unix timestamp when the current time window resets and the rate limit count is refreshed.This information is also included in the headers of every API response. Monitoring these headers (X-RateLimit-Remaining
and X-RateLimit-Reset
) is crucial for applications to manage their request rate effectively and avoid hitting limits.
When an application or user exceeds a rate limit, GitHub's API will return an error response. This typically includes:
403 Forbidden
or 429 Too Many Requests
HTTP status code.X-RateLimit-Reset
header indicating when the limit will reset.Retry-After
header suggesting how long to wait before retrying.Subsequent requests made before the reset time will continue to fail with the same error.
Effectively managing GitHub rate limits is essential for building stable and reliable applications. Practical strategies include:
X-RateLimit-Remaining
and X-RateLimit-Reset
headers in every API response. Implement logic to pause requests if the remaining limit is low and wait until the reset time.If-None-Match
(with ETag) or If-Modified-Since
headers when fetching resources that might not have changed. If the resource hasn't been modified, the API returns a 304 Not Modified
status without counting against the rate limit (or counting significantly less).Retry-After
header or until the time indicated by X-RateLimit-Reset
before making further requests. Implement an exponential backoff strategy for retries.By implementing these strategies, applications and scripts can operate efficiently within GitHub's rate limits, ensuring consistent access to the platform's services.