Score subject lines for mobile length and spam triggers before you hit send.
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Transactional · Action-Oriented & Direct — Move the reader to the next concrete step.
Appears after you run
Inbox before send
Check mobile length and common spam triggers before you ship the campaign.
An email subject tester scores subject lines for mobile length and spam triggers before you send. Critical words should sit in the first about 35 characters. Flags like “Re:” and “Free” are common preview-spoof or spam patterns — use them only on purpose. It is not a deliverability or inbox-placement predictor.
Paste one subject per line, rewrite flagged lines, re-test. Pair with Brand Voice Checker if the line must match guidelines.
Score subject lines for mobile length and spam triggers before you hit send.
Paste subjects one per line, review scores and warnings, rewrite flagged lines, and re-test. Scoring is local. It does not send mail or check your domain reputation.
Paste subjects (one per line).
Review scores and warnings.
Rewrite flagged lines and re-test.
They are common spam and preview-spoof patterns. A fake Re: looks like a thread the recipient never started. Free is overused in junk. Use either when it is true and intentional — the flag is a warning, not a ban.
No. Inbox placement depends on domain, list quality, and filters this page cannot see. The tester only checks the subject string. Clean the line, then watch actual placement in your ESP.
An email subject tester scores subject lines for mobile length and spam triggers before you send. Critical words should sit in the first about 35 characters. Flags like “Re:” and “Free” are common preview-spoof or spam patterns — use them only on purpose. It is not a deliverability or inbox-placement predictor.
They are common spam and preview-spoof patterns. Use them only when intentional.
Score subject lines for mobile length and spam triggers.
Scans and counters stay in the browser. Model rewrites spend OmniKit credits and send only the text needed for that job — not a training opt-in.
Keep measuring in the same cluster — or jump to the next decision.
Email Subject Tester lives at omnikitapp.net/tools/email-subject-tester. Score subject lines for mobile length and spam triggers before you hit send. Use it as an operator page, then confirm invoices, policies, or published facts on the source. OmniKit does not sell detector evasion or ranking guarantees.
