Hong Life CalculatorsUnderstanding the click-through rate (CTR) calculator — concept and principle
Click-through rate (CTR) is the percentage of people who clicked after seeing your ad, search listing, email link or banner. It is the quickest signal of whether a message is relevant and attractive to the people who see it, and it links impressions to traffic: impressions × CTR = clicks.
How it is calculated
CTR = clicks ÷ impressions × 100
- Clicks: the number of clicks on the ad or link in the period.
- Impressions: the number of times it was shown in the same period.
The result is a percentage. For email, the same idea is often calculated on delivered emails instead of impressions, so make sure you know which base a reported CTR uses.
The principle
CTR is a simple proportion: out of every 100 times the ad is shown, how many result in a click. It behaves like a success rate, so it can be compared across ads of very different sizes. Because many ad auctions reward relevance, a higher CTR can also help lower the price you pay per click. And since CPC = CPM ÷ (1,000 × CTR), raising CTR at the same CPM directly cuts the cost of each click.
Worked example
- Inputs: clicks 450, impressions 30,000.
- CTR = 450 ÷ 30,000 × 100 = 1.5%.
- In other words, about 15 clicks for every 1,000 impressions.
- If the same ad got 60,000 impressions at that rate, you could expect about 900 clicks.
How to read the result
There is no universal good CTR. Search ads, where people are actively looking, usually achieve higher CTRs than display banners, and CTR varies with position, format, audience and industry. Compare CTR across your own ads with the same format and placement, and watch the trend over time. A high CTR with a low conversion rate can mean the ad promises something the landing page does not deliver.
Common mistakes
- Comparing CTR from search, display, social and email as if they were the same.
- Reading CTR from very small samples; 3 clicks out of 100 impressions is not a reliable 3%.
- Optimising for clicks with misleading wording, which raises CTR but lowers conversions.
- Mixing date ranges or filters between the clicks and impressions figures.
Frequently asked questions
What is a good CTR?
It depends on the channel and placement. Compare with your own past results for the same format, or with benchmarks published for your specific channel and industry.
How many impressions do I need for a reliable CTR?
The more the better. With low rates around 1%, you need thousands of impressions before small differences between ads are meaningful.
Does CTR affect cost?
On many auction-based platforms, expected CTR is part of how ad quality is assessed, so better CTR can help lower costs.
Sources: Google Ads Help, Clickthrough rate (CTR): Definition · Paul W. Farris et al., Marketing Metrics: The Definitive Guide to Measuring Marketing Performance (Pearson)