Each API has its own limitation rules. These rules helps the service being more secure by returning error messages to the requests detected by the system's security rules.
Unlike other service providers, the only limits we consider is sending more than 1,000 per second.
So, you will be able to use the service as you want without any daily/monthly limits. Just DO NOT send more than 1k request per second.
Note that you can check your API usage in real-time from your account dashboard.