Mailtrack campaigns let you send up to 1000 emails in one go.
The number of emails you can send, though, depends on the limits Google has placed on your Gmail account. Please check your sending limit with Google.
You may encounter issues if you:
Go over Google's send limits.
Google thinks you're sending unsolicited emails (spam).
Google believes you're violating any other of their terms of service.
Campaigns is only available with Mailtrack Advanced. Upgrade to Mailtrack Advanced to enjoy this feature.