What makes a good email subject line?

Effective subject lines are clear, create curiosity or urgency, and set accurate expectations for what's inside the email.

How long should a subject line be?

Aim for roughly 40-60 characters so it displays fully across most email clients and devices.

Can I use this for cold outreach emails?

Yes, just describe your outreach context and choose a more professional tone for best results.

Email Subject Line Generator

Create compelling email subject lines that boost open rates for newsletters and campaigns.

Generate attention-grabbing email subject line ideas for newsletters, promotions and outreach campaigns.

How to use it

1Describe your email's topic or offer.
2Choose a tone, such as urgent, friendly or professional.
3Get a list of subject line suggestions to test.

Email details

Describe the topic and tone, then generate subject line ideas.

Topic

Tone

Audience

How this works

These suggestions come from curated templates, not a live AI model yet — smarter, fully generative suggestions are coming soon.

Subject line ideas

Our Spring Sale: what you need to know this week
48 characters
Our Spring Sale just got a whole lot easier
43 characters
The friendly way to think about our spring sale
47 characters
Open for a surprise about our spring sale
41 characters
Quick question about our spring sale
36 characters
5 minutes to a better our spring sale strategy
46 characters
Don't miss this update on our spring sale
41 characters
You asked, we answered: our spring sale
39 characters

Aim for under 50 characters so subject lines don't get cut off on mobile inboxes.

Frequently asked questions

What makes a good email subject line?: Effective subject lines are clear, create curiosity or urgency, and set accurate expectations for what's inside the email.
How long should a subject line be?: Aim for roughly 40-60 characters so it displays fully across most email clients and devices.
Can I use this for cold outreach emails?: Yes, just describe your outreach context and choose a more professional tone for best results.

Something wrong with this tool or its numbers?

Report an issue

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