Free, no sign-up
Email subject line tester
Check a subject line for what decides whether it gets opened: length on a phone, spam triggers, punctuation and personal touch.
This tool checks once. The Email Outreach Agent works on it every day.
Meet the Email Outreach Agent in Xicmo
Questions people ask
How long should a subject line be?
Under about 40 characters, so it is not cut off on a phone. For cold email, three to six words that read like a colleague wrote them work best.
More free tools
All tools48-hour free trial
Sign up today and run your whole marketing team free for 48 hours
- 600 credits to spend, no card needed
- Every agent: SEO, GEO, content, Reddit, X, email and more
- Up to 3 websites, the same as a Lite plan
- The Video Agent needs a subscription
The 48 hours start the moment you sign up.