You might have heard that images hurt your cold email deliverability - or that you need a careful 60/40 ratio of text to image to stay out of spam.
Well, we analyzed millions of cold emails to find out if that’s true. Turns out - it isn’t!
At least, not completely.
In most cases, images are perfectly safe to include in your cold emails. We’ll dig into the data to explain why, and give you tips to improve your email deliverability overall.
According to our analysis of millions of cold emails sent over a period of one month: no, there is no significant difference in deliverability between emails with and without images. So you can include images in your cold email campaigns without worrying that it will get your message sent to spam.
Let’s dig a little deeper.
To measure the deliverability of emails with or without images, we took a look at their open rates.
Why? Because if your emails are being sent to the spam folder, then your prospects are not opening them.
So if emails with images in the body text get a significantly lower open rate, that’d be a pretty sure sign that they’re getting flagged as spam.
However, when we analyzed millions of emails, there was no difference in open rates between emails with or without images.
Here’s the data:
Note: We did find that the presence of pixel trackers can slightly increase the chance of your emails being sent to spam.
But as long as the rest of your technical setup is okay, and you’re following deliverability best practices, this shouldn’t be an issue for you.
And don’t worry, we’ll tell you more about deliverability best practices later on in this article.
The 60/40 text-to-image ratio is an old rule of thumb that recommends emails be 60% text and 40% image, or they'll get flagged as spam. It comes from spammers using images instead of text to avoid spam filters. However, studies show that this rule is largely outdated.
According to one study, only emails with 500 characters or less risk landing in spam if the ratio of text to image is off.
If your email is at or above 500 characters, including anywhere from zero to three images will have no positive or negative effect on your deliverability.
If your email is below 500 characters, then adding one image can help it stay out of spam. So, in this case, adding an image to short emails can actually help you avoid spam.
However, adding more than one image to an email under 500 characters doesn’t make any significant change.
In any case, it’s a good rule of thumb to keep your emails at or above 500 characters. According to our data, the sweet spot is right around 120 words (roughly 700+ characters).
To learn more about the best length and formatting of your cold emails, read this guide on how long your cold emails should be.
Including a GIF in your cold email has a slightly higher chance of hurting your email deliverability than including images. That’s because if the file size of your emails is too large, it can trigger spam filters. GIFs have larger file sizes than images and have more of a risk of arriving poorly formatted in your prospects’ inboxes.
To double check, we ran the same analysis of millions of emails, this time testing if having GIFs in the body text would decrease open rates.
In fact, it does.
Emails with GIFs had a lower open rate on average than emails without GIFs. 👇
So avoid adding GIFs to your email campaigns if you’re worried about deliverability.
In general, email content has a small effect on your email deliverability. Larger factors like your technical setup and sender reputation have a more important effect on your deliverability than content questions like images or GIFs in your cold emails.
Your technical setup is what email providers use to verify and validate your sender identity. And to make sure you’re neither a spammer nor a scammer.
So having a complete technical setup is key to staying out of spam.
Your technical setup includes:
❒ SPF: Sender Policy Framework verifies that your emails have been sent from your domain
❒ DKIM: DomainKeys Identified Mail guarantees that your emails are not changed after they are sent
❒ DMARC: Domain-based Message Authentication, Reporting & Conformance helps protect your domain from attacks, phishing emails, etc.
❒ MX Records: Mail exchange Record helps providers know what servers accept emails for your domain. Without it, you won’t be able to receive emails
❒ Custom Tracking Domain: Allows you to track open and click rates in your emails safely
Here’s what those tests look like on the lemwarm warm up and deliverability dashboard ⬇
Your sender reputation is a score that email providers assign to your domain - the better it is, the more likely you’ll land in the inbox. And the worse it is, the more likely you’ll land in spam.
A variety of factors go into your sender reputation, like if individuals have reported you as spam before, you have a high email bounce rate, or you haven’t warmed up your domain.
A great way to protect yourself from getting flagged as spam and harming your sender reputation is to warm up your domain.
This means gradually increasing your sending volume to avoid triggering email providers. Because if you haven’t been sending emails and suddenly send 100s of emails daily, it can look like spam.
While doing your email warm-up, here are 3 things you should remember:
For more information, use this complete checklist to improving your cold email deliverability.
For a tool that will help you avoid spam and reach prospects’ inboxes on autopilot, try boosting your email deliverability with lemwarm.
Now you know that adding an image or two to your cold email campaign won’t get your messages sent to spam.
But do prospects actually respond to them?
According to our data: yes! Adding images to your cold emails can actually increase your reply rates, compared to emails sent without any images.
Take a look: 👇
The key to adding images in cold emails is to personalize them to your prospects.
75% of people are more likely to buy from someone who recognizes their name, recommends things based on their profile, and knows their history. Plus, 81% of consumers want brands to get to know them.
So when you add images to your campaigns, make them specific to the prospect. You can do that by adding text and image variables to the visual itself.
Take a look at this full breakdown of how to use images in your cold email campaigns.
To wrap things up, here’s everything to keep in mind about how images in cold email impact your deliverability:
P.S. One certain way to keep your emails out of spam is to use a warm-up and deliverability booster. Without one, you’re at a much greater risk of losing credibility and replies.