If you send marketing emails you often like to send them as fast as possible. While this is great in theory it’s often not recommended for your general email marketing strategy.
Find your throughput rate.
First, you need to know how many emails your server can send within a second. You can find this information on the Cron tab in the settings. You must have sent emails already to get this value.
With your throughput rate we can calculate the maximum of emails you can send with one batch.
A batch is the number of emails sent from a single cron trigger. The larger your batch is the faster you send your emails but also increases the risk of server timeouts. So we need a balance between max mails at once and no server timeouts.
Next to the batch size (number of emails sent at once), the interval of your cron is important. This defines how often a batch is triggered. By default, it’s every 5 minutes which is 12 times within an hour.
Assuming you send 20 emails with a single batch and every 5 minutes you can send 12 x 20 emails = 240 emails per hour. If you increase the batch size to 40 you can send twice as much (480).
Since the values depend on your server as well as on your email provider it’s good to adjust these values
Automatically calculate the number of emails sent at once
If you don’t know which values are a good fit for your needs check out this article.