Open rate
email open rateOpen rate tells you what share of email recipients opened the message. It is calculated by dividing opens by delivered messages. In Finnish B2B newsletters a typical level is 25–45 %.
Good to know
Open rate mostly measures how compelling the subject line and sender are, and technical changes such as Apple’s privacy protection have made it less precise: some opens are logged even though nobody opened the message. A more reliable success metric is click rate, and ultimately the sales the newsletter drives.
Open rate also measures deliverability: if messages land in spam, no subject line helps. Sender reputation is built on list quality, so cleaning inactive subscribers improves delivery of every future send. Deliverability tools can test whether your messages land in the inbox or the spam folder before you send to the whole list.
FORMULA
How open rate is calculated
Open rate is the number of opens divided by delivered messages. Bounced messages are excluded.
Open rate = opens ÷ delivered × 100
Compare against your own history: list quality affects the number more than any single subject line.
EXAMPLE
Roughly every third recipient opened. The next question is how many clicked and how many bought.
PITFALLS
Two ways to misread open rate
Apple’s preloading is read as humans
Mail Privacy Protection opens messages mechanically, and some opens are bots. The trend in one tool tells more than the absolute level.
A subject line test is called too early
A difference across a hundred recipients is noise. A reliable test needs thousands of recipients per variant.
The list is bought, the reputation pays
A purchased address list collapses open rates and brands the sender as spam. The damage shows in every future send.
FREQUENTLY ASKED
Frequently asked questions
What is a good open rate?+
In B2B newsletters 25–45 %. Under 20 % points to a tired list or weak subject lines; over 50 % signals an engaged audience.
How do I improve open rate?+
Test subject lines, send from a recognisable sender name, clean inactive subscribers off the list and send when your audience reads their mail.
Why does open rate look too good?+
Email clients’ preloading logs opens automatically. Follow the trend in one tool rather than the absolute number.
What is a good click rate in email?+
Calculated from delivered messages, 2–5 % is common and above 5 % good. Clicks tell more about content relevance than opens do.
FOR YOUR BUSINESS
Want results, not just definitions?
We go through your goals and propose channels and a budget in 30 minutes, free of charge.
FOR STUDENTS AND NEWCOMERS
Learn the terms, then come and put them to work
The glossary is free study material. Go deeper in our training, and if you want to work in the field, our growing team is looking for people.
Maintained by the VSCY editorial team · Updated 6 Aug 2026 · Part of the marketing glossary (99 terms)
