What is Split Testing?

Split testing in marketing and web analytics is synonymous with A/B testing: comparing two or more variants (creative, landing page, headline, targeting) on comparable audience segments while measuring differences in CR, ROI, EPC, CTR, and related KPIs.

How an experiment works

  1. State a hypothesis (“a red CTA button will beat green on CR”).
  2. Split traffic between variants A and B (often 50/50 or 90/10 while validating).
  3. Collect enough data (clicks, conversions).
  4. Compare results, keep the winner, or run another round (A/B/C).

Without sufficient sample size, random CR swings can look like a win for the weaker variant.

What arbitrage teams test

  • Creatives — image, headline, first video frame, ad copy.
  • Landings and pre-landings — layout, length, order form, social proof.
  • CTA — button copy, color, placement.
  • Offers — different payouts or products on the same source.
  • Targeting — audiences, placements, GEO (mixing factors complicates interpretation).

Trackers often implement splits with weights in a flow: 50% to landing A, 50% to B; sub IDs record which variant received the click.

Multivariate and sequential tests

Changing several elements at once is multivariate testing and needs more traffic. Sequential tests (creative first, then landing) are easier to read but slower.

Limits

Ad platforms offer native A/B tools; policies forbid using “tests” to swap offer substance after approval. Split testing compares compliant variants within source and advertiser rules.

Split testing is a core optimization method; without it, buyers rely on intuition while EPC and ROI can hide a losing variant that accidentally received cheaper traffic.

See also: ad creative, landing page, CR, tracker.