is A/B Testing qa, marketing, or advertising, or all?
Short answer: A/B testing is all three — but lives in different places depending on what you’re testing.
A/B Testing = QA + Marketing + Advertising (Context Matters)
| What You’re Testing | Primary Owner | Why |
|---|
| Ad creatives, copy, targeting, bids | Advertising (Paid Media) | Optimize spend, CTR, ROAS |
| Landing pages, CTAs, forms, UX | Marketing (Growth/Conversion) | Boost sign-ups, SQLs |
| Code changes, bugs, performance | QA / Engineering | Ensure functionality |
Real-World Startup Breakdown
| Test Example | Bucket | Goal |
|---|
| “Button color: Blue vs Green” on LP | Marketing | ↑ Conversion rate |
| “Headline A vs B” in Google Ads | Advertising | ↓ CPC, ↑ CTR |
| “New checkout flow breaks on mobile” | QA | No bugs in prod |
Who Runs It? (By Team Size)
| Team Size | Owner |
|---|
| < 5 people | Founder / You (wear all hats) |
| 5–15 | Growth Marketer (runs all A/B) |
| 15+ | Split: Ads → Media Buyer; Site → Growth; Code → QA |
Pro Tip
- Tool overlap: Use Google Optimize / VWO (mktg), Facebook Experiments (ads), Split.io (QA).
- One source of truth: Tag tests with
ad_test_01, lp_test_02, feat_test_03 → avoid confusion.
TL;DR:
A/B testing is a method, not a department.
- Advertising tests ads
- Marketing tests funnels
- QA tests code
→ All use the same scientific process.