Marketing
Email Subject Line Tester
Analyze your email subject line for character length, spam trigger words, and emoji count before sending your campaign.
47 chars · 0 emojis
47/50
Length
Ideal: 30–50 chars
0
Emojis
0–1 is safest
1
Spam triggers
Fewer is better
Deliverability score: 2/3
Decent — consider shortening or removing spam trigger words.
Detected spam trigger words
free
Inbox preview
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Frequently Asked Questions
Quick answers to common questions
What is the ideal subject line length?+
30–50 characters display well on mobile. Most clients truncate around 60 characters.
What spam words are checked?+
Common trigger words like "free", "urgent", "act now", "guarantee", and others that filters often flag.
Do emojis affect deliverability?+
Excessive emojis can trigger spam filters. One emoji is usually safe; three or more increases risk.
Is this a guarantee of inbox placement?+
No. This is a heuristic check. Sender reputation, content, and authentication also matter.