As the Google Drive API is a shared service, we apply quotas and limitations to make sure it's used fairly by all users and to protect the overall performance of the Google Workspace system.
 Notifications 
delivered to the address specified when
opening a notification channel don't count against your quota limits. However,
calls to the  changes.watch 
 
,  channels.stop 
 
, and  files.watch 
 
methods do count against
your quota.
If you exceed a quota, you'll receive a  403: User rate limit
exceeded 
 
HTTP status code response. Additional rate limit checks on the
Drive backend might also generate a  429: Too many
requests 
 
response. If this happens, you should use an exponential backoff
algorithm 
and try again later. Provided you stay within the
per-minute quotas below, there's no limit to the number of requests you can make
per day.
The following table details the query limits:
| Per 60 seconds | 12,000 | 
| Per 60 seconds per user | 12,000 | 
|---|
Resolve time-based quota errors
For all time-based errors (maximum of N requests per X minutes), we recommend your code catches the exception and uses a truncated exponential backoff to make sure your devices don't generate excessive load.
Exponential backoff is a standard error handling strategy for network applications. An exponential backoff algorithm retries requests using exponentially increasing wait times between requests, up to a maximum backoff time. If requests are still unsuccessful, it's important that the delays between requests increase over time until the request is successful.
Example algorithm
An exponential backoff algorithm retries requests exponentially, increasing the wait time between retries up to a maximum backoff time. For example:
- Make a request to Google Drive API.
- If the request fails, wait 1 + random_number_millisecondsand retry the request.
- If the request fails, wait 2 + random_number_millisecondsand retry the request.
- If the request fails, wait 4 + random_number_millisecondsand retry the request.
- And so on, up to a maximum_backofftime.
- Continue waiting and retrying up to some maximum number of retries, but don't increase the wait period between retries.
where:
- The wait time is min(((2^n)+random_number_milliseconds), maximum_backoff), withnincremented by 1 for each iteration (request).
-  random_number_millisecondsis a random number of milliseconds less than or equal to 1,000. This helps to avoid cases in which many clients are synchronized by some situation and all retry at once, sending requests in synchronized waves. The value ofrandom_number_millisecondsis recalculated after each retry request.
-  maximum_backoffis typically 32 or 64 seconds. The appropriate value depends on the use case.
The client can continue retrying after it has reached the maximum_backoff 
time.
  Retries after this point don't need to continue increasing backoff time. For
  example, if a client uses a maximum_backoff 
time of 64 seconds, then after reaching 
  this value, the client can retry every 64 seconds. At some point,
  clients should be prevented from retrying indefinitely.
The wait time between retries and the number of retries depend on your use case and network conditions.
Pricing
All use of the Google Drive API is available at no additional cost. Exceeding the quota request limits doesn't incur extra charges and your account is not billed.
Request a quota increase
Depending on your project's resource usage, you might want to request a quota adjustment. API calls by a service account are considered to be using a single account. Applying for an adjusted quota doesn't guarantee approval. Quota adjustment requests that would significantly increase the quota value can take longer to be approved.
Not all projects have the same quotas. As you increasingly use Google Cloud over time, your quota values might need to increase. If you expect a notable upcoming increase in usage, you can proactively request quota adjustments from the Quotas page in the Google Cloud console.
To learn more, see the following resources:

