Email Subject Line Optimizer

Score email subject lines 0-100 with heuristics for length, spam triggers, emoji and personalization.

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Overview

Scores each email subject line from 0-100 using transparent heuristics and lists the factors that helped or hurt plus concrete suggestions. It checks ideal length and word count, emoji use, ALL-CAPS, spam-trigger words, personalization tokens, numbers, questions and excessive punctuation. Built for email marketers refining open rates; it is heuristic, not AI.

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