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Email subject line tester

Subject lines are one of the most important factors in determining whether or not your email gets read. Get better open rates by subject line testing before you send. We recommend using a subject line tester or A/B testing your messages with Mailgun.

Email subject lines affect email open rates

Think about it: how many times have you deleted an email based on its subject line? We all lead busy lives and have crowded inboxes. Our email decisions are often made for the sake of efficiency. And your company’s email recipients are no different. When they scan their inboxes, they are looking for one of two things: emails from known senders or emails with engaging subject lines that pique their interest. So if the goal is to have email clients open your emails and click through to your website to sign up for a mailing list or make a purchase, you’ve got to make your email subject lines count.

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Choose the perfect subject line for your email campaigns

It doesn’t matter if you think you have a high-impact email message if people don’t read it. The length and word choice of your subject line can mean the difference between open emails and staying out of spam filters and junk folders. What mood are you trying to evoke? Serious? Humorous? What is the purpose of your email? An announcement? A request? Whatever it is, your subject line should communicate it.

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Test your subject lines for better response rates

Just as you would test a marketing email to gauge its delivery success or its visual rendering when viewed through different email clients, you need to test subject lines to make sure they are both informative and engaging. This may seem like a tall order, but it has an important payoff. Testing is always recommended for marketing emails, but testing titles should also be a priority. Just as you want to know how your email is going to display to the user once, you need to know where your title might truncate. Will your customer understand your purpose? Will your persona come through? Have you looked at competitors to assess ideal keywords and phrase length? If not, now is the time. Use one of the many testing tools to assess your subject line content and form.

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Send with the best email service provider

Mailgun’s email program offers the service and support that you need to grow and sustain large-scale marketing campaigns. We also ensure best-in-class delivery rates that will make sure your email marketing campaigns arrive in their target inboxes. Our interactive dashboard offers analytics to help refine your marketing strategy – track when your emails are opened and how – and then make adjustments to your marketing strategy as needed.

Check out our plans to bundle together features for better deliverability. For businesses that send over 100,000 emails.

Other features

Explore beyond subject lines

Mailgun has a variety of features for companies to test their email subject lines.

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