How does click tracking work?

Click tracking measures when recipients click links in your email. The mechanism involves URL replacement and redirect servers.

How it works:

1. When you create an email, links point to your actual destinations (https://yoursite.com/product)

2. The ESP replaces these with tracking URLs (https://track.esp.com/click?id=abc123)

3. The tracking URL encodes the original destination and a unique identifier for the recipient/campaign

4. When someone clicks, their browser hits the tracking server first

5. The tracking server logs: who clicked, when, which link, IP address, user agent

6. The server immediately redirects to the original destination (HTTP 301 or 302)

The recipient lands on the intended page; the redirect happens so fast they don't notice. Meanwhile, you get data: click counts, click rates, unique vs total clicks, and individual subscriber activity.

Privacy considerations: Click tracking reveals recipient behavior. Some users block tracking or use privacy tools. Regulatory frameworks like GDPR require disclosure of tracking practices in privacy policies.

Potential issues: Link wrapping can trigger security filters that inspect redirects. Very long tracking URLs sometimes break in email clients. Custom tracking domains mitigate some of these concerns.