There are two ways to do it: through the GUI or though the API.
If you are logged in, you can go to My Account, then at the Query Usage tab you will see your Plan limit and your Consumed queries.
If you make a request through the API, you’ll get two headers that show your current consumption:
- X-Query-Limit-Limit: Your current query limit.
- X-Query-Limit-Remaining: Amount of queries your account has left to use.