What makes a good email subject line?

Optimal length is 30-50 characters, uses personalization ('you'/'your'), contains power words, avoids spam triggers, and optionally includes one emoji.

What are spam trigger words?

Words like 'FREE', 'URGENT', 'ACT NOW', 'LIMITED TIME', and 'CLICK HERE' that email spam filters commonly flag.

Should I use emojis in subject lines?

One emoji can help stand out. Three or more looks spammy and may trigger filters.

Email Subject Line Tester

Analysis

Test email subject lines for spam risk, personalization, and engagement with a 1-100 score.

100% client-side processing

100% client-side — your text never leaves your browser

Input

0 characters|0 words|0 lines

Output

0 characters|0 words|0 lines

How to Use Email Subject Line Tester Online

Paste your data into the input field above
The result appears instantly in the output area
Click "Copy" to copy the result to your clipboard

Test email subject lines for spam risk, personalization, and engagement with a 1-100 score.. Runs 100% client-side — no data is sent to any server.

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Frequently Asked Questions

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