5 ways to improve your subject lines

How to Boost Your Email Open Rates with Punchy Subject Lines

Dear friend,

Happy New Year!

In 2023, I discovered this amazing book named "Copywriting Secrets" by Jim Edwards.

I devoured it like a starving pirate, staying up late until my eyes burned!

The book was a treasure map to a new world where words could move people to action.

I learned that as a copywriter, you must write persuasively and arouse interest in the reader to generate conversions and sales.

From commercials on TV, to advertisements on YouTube, and around the internet I started seeing copywriting everywhere!

In copywriting, you learn how to write a great hook to catch your reader’s attention.

With your newsletter, subject lines and preview texts get your reader's attention and motivate them to open the email.

Fail to master this skill and your newsletter won't get read.

But if you master this skill, your subscribers will eagerly open your next email.

So, let’s dive into the secrets to writing compelling subject lines and preview texts.

Subject line

64% of recipients decide to open or delete emails based on subject lines (Source: HubSpot).

Compelling subject lines stop readers mid-scroll, enticing them to dive in.

Bad subject lines are boring, too long, or don't stand out in your reader's inbox.

Finding the sweet spot for length can vary, but aim for 30-50 characters (4-7 words).

Consider what your audience cares about and what your reader's deepest desires are to write effective subject lines.

Preview text

Preview text adds a hint of what's in store like a cliffhanger.

Some readers might only see a sentence or two, others won't see any at all depending on what platform they use to check email.

To be safe, keep it short: aim for under 90 characters.

Here are five easy ways to create compelling subject lines and preview texts:

1. Think about psychology and experience

Think like your reader and put yourself in their shoes.

If they perceive your newsletter as being valuable and relevant to them, they will likely open your email.

Styles that Work: Make your subject lines pop with…

  • Entertainment: Add a sprinkle of fun, humor, or surprise.

  • Curiosity and Urgency: Create a sense of wonder or a little rush.

  • Personal Touch: Speak to what your reader wants to achieve in life.

Personalize the Experience: Use the recipient's name or remind them of past interactions if possible.

People love things that feel tailor-made for them.

Say “No” to Spammy Tactics: Avoid ALL CAPS, too many exclamation marks, or misleading information.

Avoid words like Free, Sale, and Act Now as they can trigger spam filters.

I like to get ideas from fast food advertisements and book subtitles.

I also took a psychology crash course to understand how we think.

2. Study great email copywriters

Subscribe to newsletters in your niche.

Learn from the pros and other creators in your industry.

Create a Swipe File: A swipe file is a special collection of tested and proven marketing content, like a treasure chest.

Create a swipe file of the most compelling subject lines you find by using tools like Notion or Google Docs.

Spy on Your Inbox: Look at your inbox for ideas to build your swipe file.

Add the subject lines that stand out and make you curious.

Subscribe and Learn: Join newsletters on your favorite topics.

Even join a few outside of your niche to see how other businesses use email.

Here are three amazing copywriters I follow for newsletter inspiration: Dave, Redim, and Jeremy.

3. Test and improve

Try different approaches and see how your audience responds.

Timing: Test sending emails at different times and days, considering the time zones of your audience.

Some platforms like Beehiiv have analytics to show when most of your audience opens emails.

Length: Experiment with varying subject lines and preview text lengths.

Test which length receives better engagement from your audience.

Curiosity: Craft subject lines that evoke curiosity without giving away too much.

Test the effectiveness of curiosity-driven versus more direct messaging.

I usually aim for 40-50 characters, 6 words or less on subject lines.

Sometimes, I tease in my subject lines or tell you exactly what you’ll get if you open.

4. Use a subject line grader

Omnisend is a free tool to assist you with writing high-performance subject lines.

AIPRM or ChatGPT can be used as subject line graders and generators to help you come up with ideas.

These tools give you suggestions to improve with real-time feedback.

I use ChatGPT and Google Search (looking at blog post titles on the 1st page of results) to get ideas.

Then, I paste my subject line into Omnisend to get a 90 or above score.

5. Try AI for brainstorming

AI tools like ChatGPT, Bard, and Grok can help save time in generating ideas while also sharpening your subject lines and preview text.

Try these prompts to speed up ideation:

Prompt 1:

A great email subject line stops readers mid-scroll, enticing them to dive in. The topic of this newsletter is copywriting tips for beginners. Give me 12 great subject lines with the previous definition. Make 6 of them statements and the other 6 open-ended questions. Each subject line should have between 6 to 8 words in total. Don't use any words over the 3rd-grade reading level.

Prompt 2:

Act as an expert copywriter writing a newsletter. A great email subject line stops readers mid-scroll, enticing them to dive in. Study the tone and core message of the email below. Provide 10 great subject lines according to the previous definition. Also, write a short email preview text, between 70 and 90 characters in total length. The subject lines should be between 6 to 8 words total in length. Don't use any words over the 3rd-grade reading level: [copy & paste your email here]

I use AI for brainstorming subject lines, sharpening my preview text, and making content more snappy.


It’s time to build your dream business, connect with your audience, and make a difference in the world.

Start working on what we've covered today.


Get better and get results.

If you'd like help writing your content, let's chat.

For more useful newsletter tips, stay tuned.

Your friend,