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The 6 steps to reproduce to create your Google script to send emails in bulk with Gmail. All your recipients receive a unique email sent from your email address. Be sure to abide by Gmail bulk senders guidelines. Use Gmail to send a reasonable amount of emails per day. If you have a @gmail.com email address, you can send at most 500 emails/day while with a Google Workspace account, you are limited to about 2000 emails a day. The first time you use the script it will ask for permission to send email on your behalf.