AI email subject line generator -
five options that actually get opened
Paste your email body, choose your goal, and get 5 high-performing subject lines tailored to your message. No more "Following up" or "Quick question."
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Create free account →47% of emails are opened based on subject alone
The average inbox receives over 100 emails a day. Your email has about 3 seconds and 60 characters to win attention before it's scrolled past. A better subject line isn't a small improvement - It's the difference between your message being read and being ignored.
Word.now analyzes your email body to understand the context, intent, and key ask - Then generates subject lines that match your goal, whether that's prompting a reply, communicating urgency, or being completely clear about what the email contains.
Reply rate goal
Urgency goal
Clarity goal
One size does not fit all
Cold outreach, internal updates, client proposals, and follow-ups each need a different subject line strategy. A cold pitch needs curiosity without sounding like clickbait - Numbers and specificity ("3 ideas for your Q3 pipeline") consistently outperform vague openers ("Quick question" or "Reaching out"). An internal update to a senior stakeholder needs clarity first: they need to know what the email is about before they open it, not after.
Follow-ups are where subject lines fail most often. Defaulting to "Following up on my last email" signals low priority and gives the recipient no new reason to act. The generator produces subject lines that acknowledge the prior email without repeating it, and frame the ask in a way that makes a response easy. If you also need to write the follow-up email body itself, use the Follow-up Generator. And before you send any email, the Email Tone Checker will flag passive-aggressive phrases or vague asks that could cost you a reply.
The goal setting on this tool lets you tell the AI what you actually want from the email - Not just "open it" but reply, act on something specific, or understand what it contains. That intent shapes every subject line generated. The same email body can produce very different subject lines depending on whether you need urgency or clarity as the primary driver. For a broader look at getting the most from AI in your inbox, see the best AI email assistants compared.
Subject line patterns by use case
Cold outreach subject lines
Specificity beats cleverness. "3 ideas for {company}'s onboarding emails" outperforms "Quick question" because it proves you did homework before asking for attention. Keep it under 50 characters so nothing truncates on mobile, name the value not the meeting, and never fake a reply with "Re:" - it wins the open and loses the trust.
Internal and team update subject lines
Lead with the category and the action: "Q3 budget - approval needed by Friday" tells a busy stakeholder what it is, what you need, and when, before they open it. For FYI-only emails, say so ("Launch metrics - no action needed") and your action-required emails start getting opened faster because the label means something.
Follow-up subject lines
Give a new reason to act instead of restating the old one. "Updated pricing for the option you preferred" reopens a stalled thread; "Following up again" buries it. Reference what changed since the last email - a deadline, a new detail, an easier ask - and keep the original thread subject only when the recipient needs the context to recognize you.