# Click-through rate (CTR)

> The percentage of delivered messages that produced at least one tracked link click.

- **Category:** Measurement
- **Updated:** July 2026
- **Canonical page:** [https://emailbump.com/glossary/click-through-rate](https://emailbump.com/glossary/click-through-rate)

## Definition

Email click-through rate is commonly calculated as unique clickers divided by delivered messages. Click-to-open rate uses unique clickers divided by unique openers; it answers a different question and inherits open-tracking limitations.

Tracked clicks are stronger evidence of action than pixel loads, but security scanners and link-checking systems can still create automated requests. Conversion and product events help distinguish meaningful intent.

## Why it matters

CTR connects the inbox and message experience to the next step. It can help evaluate relevance, hierarchy, offer clarity, and call-to-action placement when audience and delivery conditions are comparable.

## How it works

1. Links are rewritten through a tracked redirect.
2. A client or scanner requests the tracked URL.
3. The platform records the event and redirects to the destination.
4. Unique recipient clicks are divided by delivered messages.

## Example: CTR and CTOR are different

```text
Delivered:          9,800
Unique opens:      3,136
Unique clickers:     392
CTR:               392 ÷ 9,800 = 4.0%
CTOR:              392 ÷ 3,136 = 12.5%
```

## Common mistakes

- Calling click-to-open rate CTR.
- Counting every security-scanner request as human intent.
- Comparing newsletters, receipts, and alerts against one benchmark.
- Optimizing for clicks that do not produce a useful downstream outcome.

## Key takeaways

- Define the denominator whenever reporting CTR.
- Filter or contextualize suspected automated activity.
- Connect clicks to conversion and customer value.

## Related definitions

- [Open rate](https://emailbump.com/glossary/open-rate.md) — The share of delivered messages for which the sender recorded at least one tracking-pixel load.
- [Email subject line](https://emailbump.com/glossary/subject-line.md) — The brief message label that tells a recipient what an email is about before opening.
- [Email segmentation](https://emailbump.com/glossary/segmentation.md) — The practice of selecting recipients using shared attributes, consent, lifecycle state, or behavior.
- [Email automation](https://emailbump.com/glossary/email-automation.md) — A system that sends or changes email journeys in response to time, customer state, or events.

## Related guides

- [How to A/B test email service providers without fooling yourself](https://emailbump.com/blog/ab-test-email-service-providers.md) — A rigorous guide to ESP evaluation: experimental design, reputation confounders, delivery and latency metrics, webhook reliability, failover, cost, and migration.
- [How to design a welcome email that earns the next step](https://emailbump.com/blog/design-effective-welcome-email.md) — A practical guide to welcome-email strategy, hierarchy, copy, mobile accessibility, automation, measurement, and the product journey after the click.
- [A simple framework for writing better subject lines](https://emailbump.com/blog/write-better-subject-lines.md) — Replace guesswork with a repeatable process for subject lines that are clear, specific, and worth opening.