Open rate is the percentage of delivered messages that were opened:
Open rate = messages opened ÷ messages delivered × 100
It's used for email campaigns and, as "read rate", for channels like WhatsApp and RCS that report read receipts.
Why it matters
Open rate hints at:
- Subject line or preview effectiveness (email)
- Audience interest and list health
- Deliverability problems: a sudden drop may mean you're landing in spam
Caveats
- Privacy features such as Apple Mail Privacy Protection can load emails automatically and inflate email open rates
- Opens don't equal results, so track clicks, replies and conversions too
- Compare against your own history, not generic industry averages
How to improve it
- Write specific, honest subject lines
- Send from a recognisable name
- Segment and send relevant content
- Clean inactive subscribers
- Test send times
Example
A newsletter's open rate drops sharply after a big list import. The team checks bounces and complaints, finds deliverability issues, cleans the list, and opens recover.
Related terms
Email deliverability · List hygiene · UTM parameters
Guide: 25 subject lines that get opened.
Questions first? Chat with us on WhatsApp