Open rates are a vanity metric

If you're still measuring cold outreach success by open rates, you're doing it wrong.

Open rates are the most overrated, misleading metric in cold email. Why?
Because they’re based on tracking pixels - which are blocked by Apple, disabled by Gmail, and completely ignored by decision-makers who read emails on mobile.

So while your open rate might look healthy, you could be:

• Landing in spam

• Getting opens from bots

• Chasing false positives with zero revenue impact

It’s time to graduate from vanity metrics and start tracking what actually moves your pipeline.

The 5 metrics that actually matter

1. Inbox placement rate

If your emails aren’t landing in the primary inbox, open and reply rates are irrelevant. Use inbox placement tests to see where your emails land across Gmail, Outlook, Yahoo, and more - before scaling.

Use our free placement test tool or sign up for Warmforge to get a free placement test every month.

2. Positive reply rate

Total replies don’t matter. What matters is how many replies actually want to talk.

Track: Number of positive replies ÷ number of total emails sent

This shows you which sequences, subject lines, or ICPs actually generate intent - not just opens.

3. Cost per positive reply

This is where you tie performance to spend.

Use this formula: (Total cost of campaign) ÷ (number of positive replies)

If you're spending $500 for 5 interested replies, that’s a $100 CPR. Aim to bring this down through better targeting, cleaner data, and stronger infrastructure.

4. Cost per meeting booked

Positive replies don’t always convert. This metric shows the real efficiency of your outreach workflow - from open to meeting on the calendar.

Use tools like Salesforge or Agent Frank to automate reply handling and follow-ups, so more replies turn into meetings without manual SDR time.

5. Mailbox & domain health score

If you’re seeing a sudden drop in replies or delivery, it’s probably your reputation.
Track domain-level and mailbox-level reputation across:

• Spam complaints

• Bounce rates

• Blocklists

• Sending volume consistency

Cold email success isn’t about how many people opened your message - it’s about how many acted on it.

Track performance like a real operator:

• Focus on replies, meetings, and cost per conversion

• Monitor infrastructure health and domain reputation

• Use tools that give you actual visibility - not vanity

If you’re not sure where to start, reply to this email and we’ll help you audit your setup, free.