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Split Testing

Running controlled experiments to compare different versions of ads or settings.

Definition

Split testing (A/B testing) compares two or more versions to determine which performs better on specific metrics.

What to Test

  • Creative variations
  • Copy variations
  • Audience segments
  • Placements

Rules

  • Test one variable at a time
  • Sufficient sample size
  • Statistical significance

See A/B Testing and How to Test Facebook Ads.

Why It Matters

Split testing (A/B testing) is the scientific method of advertising — comparing two or more variations to determine which performs better. It removes guesswork from your decisions and lets data drive optimization. Consistent split testing across creatives, audiences, and landing pages is how winning advertisers maintain and improve performance over time.

Examples

  • •Testing two different headlines on the same ad to see which drives higher CTR
  • •A landing page split test comparing a long-form page vs a short-form page for conversions
  • •Testing a video ad against a static image ad with identical copy and targeting

Common Mistakes

  • ✕Testing too many variables at once, making it impossible to attribute improvements to a specific change
  • ✕Ending tests too early before achieving statistical significance (usually 95% confidence)
  • ✕Not documenting test results and losing valuable learnings for future campaign decisions
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