Cold Email Subject Line Lab
Generate honest subjects and test them.
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Write and evaluate subject lines for cold emails. Offer and recipient role: [OFFER_AND_RECIPIENT]. The email's main idea: [MAIN_IDEA]. Brand tone: [TONE]. Past subject lines and results (open and reply rates; if known): [PAST_RESULTS]. Return a table of 24 options: Subject | Technique | Length | Risk (misleading, spammy, vague) | Best for. Techniques: specific question; recent event reference; mutual connection; benefit with a number (only if true); curiosity gap that the email resolves; direct request; short and lowercase; role-based; resource offer; follow-up reference. Rules: honest and relevant to the content; under 50 characters when possible; avoid all caps, excessive punctuation, "Re:" or "Fwd:" tricks, false urgency, and spam trigger phrases; avoid including the recipient's name unless it adds value. Then select the best five and explain why; propose a test design (one variable at a time, equal splits, minimum sample of a few hundred per variant, and a note that open rates are unreliable because of privacy features, so use reply rate as the main metric); write matching preview text; and provide a log to record results and learnings. Do not promise results.
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