Subject Line Scorer · Free tool, no sign-in
Your subject line gets one second to earn the open.
Paste the subject line you were about to send, and the preheader beside it. You get a score out of 100 and the reason behind it.
Watch it work
What it does
How it works, step by step.
- Paste your subject lineAdd the preheader too if you have one.
- Read your scoreIt is scored out of 100 on length, triggers, power words, spam safety and reader focus, with a plain explanation.
- Check the inbox rowSee how the subject and preheader look on a phone and on a desktop.
- Try a rewritePick an angle from ten and get the line rewritten around it.
What you get and who it is for
Anyone who writes email to a list and wants a second opinion before pressing send.
Reasons, not just a number
Every point of the score is explained in plain English.
Preheader check
The preview text is checked beside the subject.
Private
It runs in your browser. Nothing is sent anywhere.
What it costs
- Everything
- Free, with no sign-in.
- AI and credits
- None used. It runs in your browser, with no AI calls.
Straight answers
Do I need an account?
No.
Is my subject line stored?
No. The scoring runs in your browser and nothing is sent.
Does it use AI?
No. The scoring and rewrites are built into the page, so it does not use your AI allowance.
What about the email body?
Use Spam Check for the body. It scans the subject, preheader and body together.