How to measure cold email results: opens, replies, deals
Which cold email metrics really matter, why open rates often lie, how to calculate reply and bounce rates, and when to change your copy or your audience.
The main cold email metric is the reply rate, not the open rate. Opens help you spot deliverability problems, bounces show the quality of your list, and replies and deals show whether your offer works. Here's how to calculate each number and what to do with it.
The cold email funnel
- Sent: how many emails went out.
- Delivered: sent minus bounces (addresses that don't exist).
- Opened: how many people opened the email (approximately).
- Replied: any reply, including a no.
- Interested: replies that could turn into a conversation.
- Deals: those who became clients.
Bounces: the quality of your list
Bounce rate = bounces / sent.
Keep it below 2–3%. A higher number means your list has many dead addresses, and mail providers will start lowering your inbox's reputation. The fix: verify addresses before sending.
Opens: an indicator, not a goal
Opens are counted through an invisible tracking pixel in the email. The number isn't precise:
- Apple Mail loads images in advance, so an email counts as opened even if the person never saw it;
- some email clients block images, so real opens aren't counted.
Treat opens as a signal: if there are almost none, your emails probably land in spam or the subject line doesn't work. How to check deliverability is covered in why emails go to spam.
Replies: the number that matters
Reply rate = replies / delivered.
Count every reply, even "not interested": the person read the email and reacted, so the copy and the delivery work. Count interested replies separately; they show whether your offer lands.
How to compare variants
- A/B test. Split the audience in two and send two versions of the email. Change one thing at a time: the subject, the first sentence or the offer.
- By lead grade. Compare replies from A, B and C leads. More in A, B and C lead grades.
- By follow-up. See how many replies come from the first email and how many from reminders. How to write them is in cold email follow-up.
What to do with the numbers
| What you see | Likely cause | What to change |
|---|---|---|
| Many bounces | Old or unverified list | Verify addresses before sending |
| Almost no opens | Spam or a weak subject | SPF/DKIM/DMARC, fewer emails a day, a new subject |
| Opens but no replies | The copy or offer doesn't hook | Shorter email, a specific detail, an easy question |
| Replies are "not interested" | Wrong audience | Another niche, city or lead grade |
How many emails you need for conclusions
At least 100–200 emails per variant. With small numbers one reply moves the percentage a lot, and it's easy to draw the wrong conclusion.
In Vibe Hunters each campaign's details show how many emails were sent and opened, how many replies and errors there were, and you can read the replies and answer them right in the campaign chat.
FAQ
Why are open rates inaccurate?
Opens are counted through an invisible image in the email. Apple Mail loads images in advance and some providers block them, so opens can be both inflated and understated.
How many emails do I need before drawing conclusions?
At least 100–200 emails per copy variant and audience. With 20 emails, one or two replies already double the percentage.
What should I change first: the copy or the audience?
If people open but don't reply, change the copy and the offer. If there are barely any opens, check deliverability and the subject line. If they reply "not interested", change the audience.