If you are logged in, you can go to My Account. There you will see your current query usage and compare it to your plan limit for the month. You will also see the number of custom models active under your account and the limit for that as well.
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.