How to check your sending limit in Gmail
While you can always count through your sent messages folder in Gmail, there’s not a clear way to track your daily sending limit within your Gmail account.
Using a tool like Streak’s mail merge can help you track how many messages you’ve sent via mail merge so you know exactly how close you are to the daily sending limit and when you’ll be able to send additional messages.
Source: https://www.streak.com/post/gmail-daily-sending-limit?utm_source=customerio&utm_medium=newsletter#check-your-sending