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IP and Domain Email Warmup Calculator

This tool will help you estimate the number of emails, per hour, you should send with when moving to a new email marketing provider. Sending in batches is a feature supported in all Bento accounts.

Learning how to warmup your domain and IP for email marketing couldn't be easier with our free calculator.

You're here because of two reasons:

  • You've just migrated to a new email marketing platform and want to ensure you maximize your engagement metrics and not get yourself spam listed.

  • Your open rates aren't what they used to be and want to restart the warmup process on a new IP or domain.

Either way, you've come to the right place.

Above we've created a simple calculator for you to use to estimate the maximum hourly rate you should send out your marketing emails to your list.

Not all email marketing platforms will give you the ability to throttle your email sending so make sure to switch to one that does (like Bento).

In Bento, you can throttle your broadcast delivery by using our batched sending feature which is baked into the creation workflow.

This allows you to divide your total subscribers up by any amount you specify and slowly drip out the emails instead of them all going out at once.

Awesome, right?

(If your email platform does not give you this ability consider switching to us or talking to our team on Discord about what a migration could look like).

A great warmup starts slow and steady.

If you've just moved over your list to a new provider, like Bento, you will want to start sending your marketing/promotional email as slow as you can stomach.

In the early days, this could be as slow as a few hundred emails per hour and nothing more.

This will mean that a broadcast you send out on a Monday could take an entire week to get out the door and completed.

Learn to be okay with this and be patient; it pays off for every single account we've seen.

A few accounts we've tracked have gone from single digit opens (less than 8%) with providers like MailChimp to 25% and beyond with Bento after a successful warmup strategy.

As the weeks go on you just keep shortening the time frame based on the recommendations above.

As for transactional email (billing, invoices, etc) you don't have to worry about as you can't really control the throttling of those. Just make sure you're not bulk importing people into your sequences unless it's really necessary for compliance.

Remember that a good warmup can take an entire month (or six).

It's entirely up to you how many months you take things slow but we've seen the best results for customers who have warmed up for an entire month — with some customers warming up o ver six months!

The larger the list the slower you want to take things.

The above calculator will give you a rough estimate on how long you should keep things slow and paced out.

After you have warmed up you still want to take things slow if you're not a frequent sender.

Are you sending out more than 2-3 times per week?

Are you sending out 10s of thousands of transactional emails per week?


Then you not a frequent sender and should pace yourself for all your marketing emails.

In the calculator above we give you an Optimal Batch Size metric. This is the hourly rate you should send your broadcast out even after you've warmed up if you want to maximize open rates and clicks.

If you have a more urgent broadcast to get out the door you can instead use the Urgent/Sale Batch Size number which is a little more aggressive.

Just remember to take things slow even after the warmup.

Moving forward, you always want to send in batches.

Once your list size starts getting very large you're going to want to always send in batches even if it's over a 2-4 hour period.

This is because, at least in Bento, you can stop a batch mid-send and make changes. This is important if you've accidently triggered a spam flag in the first batch due to a word or subject line mishap (happens!).

We also believe that the email providers like Gmail and Yahoo treat smaller sends differently as they are less risky.

If you need help reach out to Bento.

If you're struggling to put a good warmup strategy together please don't hesitate to reach out to our team at Bento and talk. We're here to help.