Click Through Rate (CTR) Calculator

Compute CTR, CIs, A/B significance, and sample sizes. Analyze multiple campaigns and export results.

CTR

3.00%

Clicks

120

Impressions

4000

95% CI

[2.51% – 3.58%]

Basic CTR Calculator

CTR and Wilson CI

CTR: 3.00%
CI: [2.51% – 3.58%]
Clicks @ lower: 101
Clicks @ upper: 143

Inverse: Clicks Needed

Clicks: 150

Inverse: Impressions Needed

Impr: 6000

A/B Test Significance

Two-proportion z-test, CI for difference

Variant A

CTR: 3.00%

Variant B

CTR: 3.66%

p-value: 0.0988
Diff (A-B): -0.66%
Relative: -18.00%
z: -1.651
CI 95%: [-1.44% – 0.12%]

Sample Size & Duration

Required impressions per variant for desired lift

nA ≈ 53,208, nB ≈ 53,208
Duration A: 3 day(s) · B: 3 day(s)

Bulk Campaign Analysis

Paste CSV/TSV (label, impressions, clicks) or upload file

Confidence:
LabelImprClicksCTR95% CI
Totals00Micro: 0.00% · Macro: 0.00%[0.00% – 0.00%]

What is Click Through Rate (CTR)?

Click Through Rate (CTR) is the ratio of clicks to impressions, expressed as a percentage: CTR = (Clicks ÷ Impressions) × 100%. It's a critical metric in SEO, PPC advertising, and digital marketing that measures how often people click on your content or ads.

Key Features

1. Basic CTR Calculator

Calculates CTR with Wilson confidence intervals for statistical reliability. Wilson CIs are more accurate than simple binomial intervals, especially with low click counts.

Example: 1,200 clicks from 50,000 impressions = 2.40% CTR [95% CI: 2.28%-2.52%]

2. Inverse Calculations

  • Clicks Needed: For target CTR + impressions, calculate required clicks
  • Impressions Needed: For target CTR + clicks, calculate required impressions
Example: To achieve 3.5% CTR with 25,000 impressions, you need 875 clicks.

3. A/B Test Significance

Compares two variants using two-proportion z-tests with configurable alpha levels (0.10, 0.05, 0.01) and test types (two-sided, one-sided).

Example: Variant A (1.80% CTR) vs Variant B (2.10% CTR) shows 16.67% relative lift with p-value 0.019 (significant at α=0.05).

4. Sample Size Calculator

Determines required impressions to detect minimum detectable effects (MDE) with statistical power. Considers baseline CTR, desired lift, alpha, power, and traffic split ratio.

Example: To detect 15% relative CTR lift from 2.5% baseline requires ~61,800 impressions per variant at 80% power.

5. Bulk Campaign Analysis

Analyze multiple campaigns simultaneously. Supports CSV/TSV import/export with format: label, impressions, clicks. Provides micro CTR (total clicks/total impressions) and macro CTR (average of individual CTRs).

Statistical Methods

  • Wilson Confidence Intervals: Superior to simple binomial intervals for CTR estimation
  • Two-Proportion Z-Test: For comparing CTRs between variants
  • Power Analysis: Sample size calculation for detecting meaningful effects

Industry CTR Benchmarks

  • Search Ads: 2-4%
  • Display Ads: 0.5-1%
  • Social Media: 1-3%
  • Email Marketing: 2-5%
  • Organic Search: 1-3%

Best Practices

  • Use 95% confidence intervals for most analyses
  • Aim for 80% statistical power in A/B tests
  • Consider practical significance, not just statistical significance
  • Use Wilson CIs for stable estimates at low counts
  • Choose two-sided tests for exploratory comparisons
  • Account for multiple testing when running many comparisons
  • Sample size depends on baseline CTR, desired lift, alpha, power, and traffic ratio
  • Bulk analysis accepts CSV/TSV format: label, impressions, clicks

Applications

  • SEO: Track CTR improvements from title/meta changes
  • PPC: Calculate required clicks for profitability
  • Content Marketing: Measure engagement across content types
  • A/B Testing: Compare ad copy, landing pages, and CTAs