Write the subject line for an email
Updated 1 September 2026
The Short Answer
An email message has a subject box above the body. Write what you want, up to 200 characters. Leave it blank and PropKaki uses your opening line instead, so an email never goes out without a subject.
The subject box appears on email messages only. Filling it in is optional.
Where is the subject box?
On the message itself, above the body — but only when the channel is email. A WhatsApp message has no subject, so the box is not there.
What happens if I leave it blank?
PropKaki uses your opening line as the subject. An email never goes out without one.
That is a real fallback, not a placeholder — so leaving it blank is a legitimate choice when the first line already says what the email is about.
How long can a subject be?
Up to 200 characters. In practice far shorter is better — a subject that is cut off in someone's inbox is worse than a plain one that fits.
Does the subject change per person?
What you write is what goes out, to everyone in that send. It is the one part of an email message that is not written per person.
If you leave it blank, each person's subject comes from their own opening line — which does differ per person, because the body does.