ToolSnippet
✍️Part of Text & String Utilities

Free Email Subject Line & Spam Score Tester

Optimize email open rates and avoid spam filters by analyzing subject line character count, spam words, and mobile preview truncation.

About This Tool

The Email Subject Line Tester grades subject line deliverability. It flags high-risk spam words (e.g. '100% FREE', 'ACT NOW', 'URGENT CASH'), tests mobile email client cutoffs (~40 characters on iPhone/Gmail app), and scores urgency and punctuation balance.

How to Use

  1. 1Enter your Email Subject Line and optional Preheader/Preview text.
  2. 2Review the overall Subject Line Score and spam risk indicator.
  3. 3Inspect the live simulated Mobile Email Inbox preview.
  4. 4Remove flagged spam words to maximize inbox deliverability.

Why Use ToolSnippet Email Subject Line & Spam Score Tester?

Prevent newsletters and transactional emails from landing in spam folders.
Optimize subject lines for mobile Gmail and Apple Mail apps.
Identify overused sales hype and excessive punctuation.
100% private in-browser analysis.

Frequently Asked Questions

What is the optimal character length for email subject lines?

The ideal length is 30 to 50 characters (or 4 to 7 words). Mobile email clients typically truncate subject lines exceeding 40–45 characters.

What triggers email spam filters?

Excessive capitalization (ALL CAPS), multiple exclamation marks (!!!), and trigger words like 'GUARANTEED', 'FREE', 'CASH BONUS', and 'CLICK NOW'.

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