AI generator · Free
Five cold email subject lines, two words or fewer.
Paste prospect context. Get five short subject lines that hit the 1 to 4 word optimal length window backed by Gong's 85M-email dataset.
The context
The more specific your email body, the better the subject.
The subjects
1 to 4 words is the optimal length window per Gong's 85M-email study.
Fill the form and click Generate. Output appears here.
Every number on this page links to a primary source
We cite original studies (Ehrenberg-Bass, RAIN Group, HubSpot, Bridge Group, Instantly, Belkins) rather than secondhand vendor blog posts. Where a stat has a known caveat, we say so.
- [1]Optimal subject length
Gong x 30MPC Cold Email Data Report 2024 (85M+ emails, via Salesloft and Lavender data): 1 to 4 words performs best; 2 words is optimal; going from 2 to 4 words drops reply rate 17.5%; one-word subjects get 87% higher reply. Backlinko's 12M-email link-building study finds 36-50 char subjects win, but that dataset is link-building outreach, not B2B sales.
Gong x 30MPC Cold Email Data Report 2024 · 2024Source - [2]Subject anti-patterns
Lavender dataset on subject-line anti-patterns: numbers in subject -46.33% open likelihood; punctuation -36%; questions -56%; first names in subject -12% replies; not using title case -30% opens.
Lavender Cold Email Benchmark Report · 2024Source - [3]Personalized subject
Personalized cold email subject lines deliver 26 to 30.5% higher open rate across SalesHandy 2024, Snov.io 2026, and Lemlist data. Salesloft sentiment research finds neutral, descriptive tone gets the most replies.
SalesHandy 2024; Snov.io 2026; Lemlist · 2024Source - [4]Cold reply baseline
Instantly Cold Email Benchmark Report 2026 (billions of emails sent Jan to Dec 2025): 3.43% platform-wide cold email reply rate. Top 25% of senders achieve 5.5%+; the elite top 10% reach 10.7%+.
Instantly Cold Email Benchmark Report 2026 · 2026Source
Cold Email Subject Line Generator FAQ
Stop testing subject lines. Test signals.
Subject A/B tests live in the noise floor. The biggest open-rate lever is whether you message during a buying signal at all.
