Free Email Subject Line Checker: Length, Mobile Preview and Spam Signals
Your subject line decides whether your newsletter gets opened. On phones, the end of a long subject is usually cut off. Enter your subject line and preheader to see how they may look and what to fix.
Everything is checked in your browser. Nothing is sent or stored.
How it may look in a phone inbox
A
Acme Inc.October update: our new service a…This month: a new service launch and where to find us in November.
Subject line tips
- Put the key words first: phones may show only around 30 to 40 characters, depending on the app and settings.
- Match the content: the U.S. CAN-SPAM Act requires the subject line to accurately reflect the message.
- Use the preheader: the preview text after the subject is a second line to earn the open.
- No fake Re: or Fwd:: Google's sender guidelines say not to use them unless the message really is a reply or forward.
About these checks
Length is measured as display width (wide characters such as Japanese count as two). Spam words aren't banned; whether mail lands in spam depends on many things, including domain authentication and sender reputation.
Skip writing subject lines
Newsletter Ready drafts the subject and the whole issue from your newest website articles. You read it and approve.
Sources
Checks and previews are estimates. Actual display depends on the email app, device and text size settings.