What is CTR?
Click-through rate (CTR) measures how often people click compared to how often they see something (impressions). It’s used across ads, search results, and emails.
Click-Through Rate (CTR) Calculator
Enter impressions and clicks to instantly calculate click-through rate (CTR) for ads, SERP results, and emails.
CTR Calculator
Calculate click-through rate (CTR) for ads, SEO, email, and more.
Results
- CTR %
- CTR (decimal)
- Category
- Clicks
- Impressions
How to Use the CTR (Click-through Rate) Calculator
Follow these steps to calculate click-through rate from your ad metrics and see both percent and decimal CTR.
Enter the number of impressions.
Type the total number of ad impressions for the period you’re analyzing (e.g., from Google Ads or your ad server report). Use whole numbers only (no commas or decimals), such as 3859. Do not use “reach”
Enter the number of clicks.
Input the total valid clicks recorded for the same period. Use a whole number and make sure clicks do not exceed impressions. Exclude known invalid/bot clicks if your platform provides that filter.
Choose display precision (optional).
Toggle the “Show decimals” option if you want to see CTR as a decimal in addition to the percentage. This is useful when CTR values are very small and you need more precision for reporting.
Review the results and category.
The calculator shows CTR % and CTR (decimal) instantly, plus a quick category indicator (e.g., Poor, Fair, Good, Excellent) to help interpret performance. Use the Traffic Breakdown to compare clicks vs. non-clicks and confirm your inputs align with your campaign report.
Frequently Asked Questions
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CTR is the ratio of valid clicks to valid impressions. In percentage form: . In decimal form: .
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Compute . As a percent, . With standard rounding, report 0.57% (decimal 0.0057).
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Impressions must be >0. Clicks and impressions must be non-negative integers with clicks ≤le≤ impressions. If impressions =0, CTR is undefined and should not be computed or displayed.
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Differences typically come from (1) which clicks/impressions are considered “valid” after filtration (e.g., bot/fraud filtering), and/or (2) rounding/display rules (number of decimals, tie-handling). The mathematical ratio is the same when inputs and rounding rules match.
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Use either consistently. Percent is common for reporting (e.g., 0.57%), while decimal form (e.g., 0.0057) is convenient for modeling and calculations.
Methodology & Sources
We compute CTR as the dimensionless ratio of valid clicks to valid impressions, then multiply by 100 for percent view: with constraint . Inputs are integers with . Counts should reflect IAB/MRC filtering and audit practices before calculation. Arithmetic uses IEEE-754 round-to-nearest, ties-to-even for display; we show percentages to two decimal places and decimal CTR to four significant digits unless otherwise specified.
Bibliography
- (2009). Click Measurement Guidelines (Version 1.0) — IAB / MRC https://mediaratingcouncil.org/sites/default/files/Standards/click-measurement-guidelines2009-2.pdfAccessed 2025-10-17
- (2019). IEEE Standard for Floating-Point Arithmetic (IEEE Std 754-2019) — IEEE https://www-users.cse.umn.edu/~vinals/tspot_files/phys4041/2020/IEEE%20Standard%20754-2019.pdf