---
title: "Free Email Subject Line Generator - AgentDock"
description: "Create compelling email subject lines that boost open rates with multiple variations for A/B testing"
url: "https://agentdock.ai/prompt-library/business/email/subject-line-generator"
docs_index: /llms.txt
---

# Email Subject Line Generator

Create compelling email subject lines that boost open rates with multiple variations for A/B testing

Category: Email

## Prompt template

```
I need compelling email subject lines that will maximize open rates.

The email is about [EMAIL_TOPIC] and the primary goal is [EMAIL_GOAL:select:drive sales,announce something,share information,get a response,build relationship,promote content,request action].

My target audience is [TARGET_AUDIENCE] in the [INDUSTRY] industry. The tone should be [TONE:select:professional,casual,urgent,friendly,authoritative,playful,formal].

Generate [NUMBER_OF_VARIATIONS:number:5-15] unique subject line variations. For each variation, use a different psychological approach such as curiosity, urgency, benefit-focused, personalization, question, number/statistic, fear of missing out, or social proof.

For each subject line provide the character count in parentheses and label the approach used. Keep subject lines under [MAX_CHARACTERS:number:30-80] characters since 85% of users read email on mobile where only 25-30 characters display fully.

Emoji usage preference: [USE_EMOJIS:select:yes include emojis,no emojis,mix of both].

If I have a specific angle or key message I want emphasized, it is: [KEY_MESSAGE?]

Format the output as a numbered list grouped by approach type. Mark the top 3 strongest performers with a star and explain why each is likely to achieve high open rates. For each starred subject line, also suggest a matching preview text (the snippet that appears after the subject line in inbox view).
```

## Variables

- Email Topic (text, required)
- Email Goal (select, required) — options: drive sales, announce something, share information, get a response, build relationship, promote content, request action
- Target Audience (text, required)
- Industry (text, required)
- Tone (select, required) — options: professional, casual, urgent, friendly, authoritative, playful, formal
- Number Of Variations (number, required)
- Max Characters (number, required)
- Use Emojis (select, required) — options: yes include emojis, no emojis, mix of both
- Key Message (text, optional)

Tags: email, subject line, open rate, marketing, copywriting, A/B testing

Open in the editor: https://agentdock.ai/prompt-library/business/email/subject-line-generator