Open Tracking vs Click Tracking
Open tracking and click tracking are the two core email tracking mechanisms. Open tracking fires when a 1x1 transparent pixel loads in the recipient's mail client. Click tracking fires when the recipient clicks a tracker-wrapped link. They measure different recipient behaviour and have different reliability characteristics in 2026.
See how this shows up in your own inbox: try Outsolvi free for 14 days, no credit card.
Both mechanisms have been with us since the early 2000s but their reliability has diverged sharply since 2021.
Open tracking
Mechanism: a 1x1 transparent pixel embedded in the email body loads when the mail client renders the message. The pixel request hits the tracker's endpoint, which logs the event with IP, User-Agent, and timestamp.
Reliability in 2026: - Heavily contaminated by Apple Mail Privacy Protection (Litmus says studies put it at 55 to 60 percent of all opens) - Contaminated by corporate security scanners too - Gmail proxy duplicates inflate counts further - Net: raw open counts include machine opens; grade each open before you trust it
Click tracking
Mechanism: every link in the email is replaced with a tracker-wrapped URL. When the recipient clicks, they hit the tracker's endpoint first, which logs the click and 302-redirects to the original URL.
Reliability in 2026: - Contaminated by Microsoft Safe Links, Mimecast URL Protect, Proofpoint TAP (every link clicked within 5 seconds of delivery by scanners) - Less contaminated than opens overall, but at large corporate domains Omnivery found 80 to 95 percent of clicks came from scanners - Filtering on IP + User-Agent + timing brings reported clicks close to actual human clicks
What each measures (post-filtering)
- Confidence-scored opens: probability the recipient at least previewed the message
- Filtered clicks: probability the recipient was interested enough to click through
Which to trust
Reply rate > filtered clicks > confidence-scored opens > raw opens. In that order.
Track real engagement, not Apple MPP noise.
Start Free TrialFrequently asked questions
Can I have click tracking without open tracking?+
Yes. Some senders disable open tracking (because it's so noisy) and rely only on click tracking. The downside is losing all engagement signal on recipients who don't click.
Do clicks count if the recipient clicks through a forwarded email?+
Yes; the click wrapper fires regardless of who clicks. Forwarding is a signal worth capturing.
Put this concept into practice
Free tools, articles, and features on this same topic.
Related glossary terms
Want accurate tracking that handles Open Tracking vs Click Tracking?
Outsolvi tracks Outlook and Gmail, grades every open as a person or a machine, and flags hot leads, from $7/user/mo billed yearly. 14-day free trial, no credit card.
Start 14-Day Free TrialNate built Outsolvi after watching every email-tracking tool he had ever used lie to him about opens. Outsolvi grades every open as a person or a machine, in Outlook and Gmail, so the number on the dashboard is one a rep can actually act on.
We update these pages when the underlying mechanics change. new mailbox-provider rules, new tracker behavior, new measurement gaps. The dates above are real revisions, not auto-touches.