Free tool

Email Subject Line Generator

Describe your email and pick a tone, and get subject line variants in seconds — then analyze each one for length, readability, and spam risk.

Guide

How to write a subject line in an email

Your subject line is one of the most important factors in determining whether your email gets opened or ignored. It should tell recipients what to expect without sounding misleading or overly promotional.

A strong subject line is:

  • Clear and specific.
  • Relevant to the recipient.
  • Short enough to display on mobile devices — typically 30 to 50 characters.
  • Honest about the content of the email.
  • Personalized when appropriate.

Before sending your campaign, ask yourself:

  • Does the subject explain why someone should open the email?
  • Would you click on it yourself?
  • Does it match what's inside the email?
  • Does it avoid unnecessary capitalization and excessive punctuation?

Our free email subject line generator helps you brainstorm ideas, but the best-performing subject lines always match your audience and the goal of your message.

Examples

20 professional email subject line examples

Whether you're sending a sales email, following up with a prospect, or announcing a product update, these examples can help you get started.

Sales and outreach
  • Quick question about your business
  • Following up on my previous email
  • Ideas to help improve your [goal]
  • Would this be useful for your team?
  • Thought you might find this interesting
Marketing and newsletters
  • Here's what's new this month
  • Your weekly update
  • New resources you might enjoy
  • Our latest product updates
  • Don't miss this week's highlights
Customer success
  • Welcome to [Company]
  • Getting started with your account
  • Your onboarding checklist
  • Your subscription has been updated
  • Thanks for being a customer
Internal communication
  • Agenda for tomorrow's meeting
  • Project update
  • Action required before Friday
  • Monthly team update
  • Welcome to the team

The best subject lines are relevant, easy to understand, and accurately reflect the content of the email. Rather than relying on clickbait or excessive urgency, focus on giving recipients a clear reason to open your message.

FAQ

Frequently asked questions

What makes a good email subject line?

A good subject line is clear, relevant, and concise. It tells recipients what the email is about while encouraging them to open it. Avoid misleading claims or unnecessary promotional language.

How long should an email subject line be?

Aim for 30 to 50 characters when possible. Shorter subject lines are easier to read on mobile devices, although slightly longer ones can still perform well if they're specific and engaging.

Can AI generate effective email subject lines?

Yes. AI subject line generators can quickly produce ideas for newsletters, sales emails, follow-ups, and promotional campaigns. However, you should always review and customize the suggestions to match your audience, brand voice, and the content of your email.