Free tool
Email warmup schedule calculator
Tell us how old your domain is and how much you want to send. Get a week-by-week warmup plan with the date you can start cold email.
Pick your options and click Build. Warmup starts at 5 emails a day and adds 2 a day up to 40.
How the schedule works
Warmup starts small and grows every day: 5 warmup emails on day one, 2 more each day, up to 40 a day. On weekends warmup drops to about 40% of a weekday, because real people email less on weekends. These are the same defaults Reachbox uses for every mailbox.
- Older domains that already send email can start cold email after two weeks of warmup.
- New domains get an extra week, because receivers have no history to judge them by.
- Cold email starts at about 10 a day per mailbox and steps up once a week until it reaches your goal.
- Warmup keeps running while you send, so good signals keep outweighing the cold volume.
When is a mailbox ready?
Dates are the earliest safe start, not a promise. A mailbox is ready when at least 90% of its warmup emails land in the inbox over the last 7 days and it has been warming for at least 14 days. If placement is lower, keep warming and fix your DNS setup first.
Warmup cannot fix broken SPF, DKIM or DMARC. Check your domain before you start. Check SPF, DKIM and DMARC →
How to send more
Most teams keep each mailbox at 30 to 50 cold emails a day. To send more, add mailboxes and spread them over a few domains rather than pushing one mailbox harder.
Work out how many mailboxes and domains your volume needs. Mailbox calculator →
Questions
How long does it take to warm up an email account?
Plan for two weeks for a domain that already sends email and three weeks for a new domain, then keep warmup running while you send. Watch inbox placement rather than the calendar: start cold email once at least 90% of warmup emails land in the inbox.
How many warmup emails should I send per day?
Start with about 5 a day and add 2 a day, up to around 40. Going faster looks unnatural to Gmail and Outlook. Fewer emails on weekends make the pattern look more like a real person.
Should I stop warmup once my campaigns start?
No. Warmup emails get opened, replied to and rescued from spam, which keeps adding good signals while cold email adds unknown ones. Keep it on for as long as the mailbox sends cold email.
How many cold emails can I send per day after warmup?
Most teams stay at 30 to 50 per mailbox per day. Start around 10, add a few each week, and add more mailboxes when you need more volume.
Is warmup free in Reachbox?
Yes. Warmup is included on every Reachbox plan and runs this schedule for each mailbox you connect, with a health score that shows when the mailbox is ready.