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Montegra Reach

Subject line checker

Type a subject line for a sales or cold email and see what might hurt it. Everything runs in your browser; nothing is sent anywhere.

What it checks

Length (short subjects read fully on phones), words and punctuation that look like marketing, all-caps words, and fake "Re:" or "Fwd:" prefixes, which are misleading and can break anti-spam laws. It's a set of rules of thumb, not a guarantee of inbox placement; see email deliverability basics for the bigger picture.