Using the tester is simple: just type or paste your subject line into the input field, and hit “Test.”
You’ll instantly receive a score out of 100, along with personalized suggestions for improvement.
You can try as many variations as you like – it’s a quick, easy way to optimize your subject lines before you hit “send.”
We’re excited to announce a huge update to our free Email Subject Line Tester, packed with new features designed to give you even more powerful insights into your email performance. We’ve gone beyond simple word counts to provide a more complete analysis.
Here’s what’s new:
Sentiment Analysis: The tool now analyzes the emotional tone of your subject line. Instantly see if your message comes across as positive, negative, or neutral, and get tips to create a more engaging tone that encourages opens.
Smarter AI Suggestions: Don’t just get generic ideas. Now, you can input your own subject line and our AI will provide improved variations tailored to your original idea. It’s like having a copywriter on demand to polish your work. When you enter your subject line (e.g., “our new products”) and select a category (e.g., “Product Launch”), the tool captures both pieces of information.
Emoji Usage Analysis: Emojis can boost open rates, but too many can hurt them. Our tester now checks your emoji count and tells you if you’ve hit the sweet spot or if you should scale it back.We built these new features to help you stop guessing and start writing subject lines that get real results.
Your subject line starts with a base score of 70 points. From there, the tester analyzes key factors that impact performance, from length and word choice to formatting and emotional tone.
Our subject line tester works by weighing both technical structure and marketing psychology, and gives you a well-rounded assessment designed to help you write subject lines that stand out for the right reasons. And the best part? It’s totally free!