<!-- SPDX-License-Identifier: MIT -->
<!-- SPDX-FileCopyrightText: 2025-2026 Marcus Quinn -->

# Conversion Rate Optimization (CRO) - AI Agent Skill

**Reading path:** New to CRO → Chapters 1-3 (foundations), then Chapter 4 (landing pages) | Experienced → Chapter 9 (pricing psychology), Chapter 16 (analytics) | Team leads → Chapter 20 (enterprise), Chapter 21 (testing masterclass).

**Full chapter index:** [cro-chapters.md](cro-chapters.md) — 25 chapters across 7 parts.

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## Core CRO Principles

**What CRO is:** The systematic, data-driven process of increasing the percentage of visitors who take a desired action. Combines psychology, design, copywriting, analytics, and UX research.

**The CRO process:**
1. **Research** - Quantitative (analytics, heatmaps) + qualitative (surveys, recordings) to identify barriers
2. **Hypothesize** - Form testable hypotheses; prioritize with PIE/ICE/RICE; define success metrics
3. **Design** - Create test variations; set up A/B or multivariate tests; verify tracking
4. **Execute** - Run to statistical significance; monitor for anomalies; don't stop early
5. **Analyze** - Statistical rigor; look beyond primary metrics; extract learnings from all outcomes
6. **Iterate** - Implement winners; document learnings; identify next opportunities

**Key formula:**

```text
Conversion Likelihood = Perceived Value / Perceived Friction
```

### Cognitive Biases That Drive Conversions

| Bias | Application |
|------|-------------|
| Social Proof | Customer counts, reviews, "most popular" badges |
| Scarcity/Urgency | Limited stock, time-limited offers (must be genuine) |
| Authority | Certifications, expert endorsements, media mentions |
| Reciprocity | Free content/tools before asking for commitment |
| Loss Aversion | Frame what users will miss, not what they'll gain |
| Anchoring | Show original price with sale price; premium tier first |
| Paradox of Choice | Fewer options, "best for most" recommendations |
| Commitment/Consistency | Start with micro-conversions, build to macro |
| Decoy Effect | Third option makes target option more attractive |

Prioritization frameworks (PIE, ICE, RICE, RICE, Expected Value): [cro-chapter-03.md](cro-chapter-03.md). Industry benchmarks by segment: [cro-chapter-02.md](cro-chapter-02.md).

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## CRO Audit Quick Checklist

**Landing Page:**
- [ ] Clear value proposition above the fold
- [ ] Single, prominent CTA
- [ ] Social proof visible without scrolling
- [ ] Page loads in <3 seconds
- [ ] Mobile-optimized layout

**Forms:**
- [ ] Minimum required fields
- [ ] Clear labels and error messages
- [ ] Progress indicator for multi-step
- [ ] Smart defaults and auto-fill

**Checkout:**
- [ ] Guest checkout available
- [ ] Multiple payment methods
- [ ] No surprise costs
- [ ] Security badges visible
- [ ] Clear shipping information

**Trust:**
- [ ] Customer testimonials with specifics
- [ ] Trust badges and certifications
- [ ] Money-back guarantee
- [ ] Clear contact information
- [ ] Privacy policy accessible

**Testing:**
- [ ] Adequate sample size calculated
- [ ] Tests run to statistical significance (p < 0.05)
- [ ] One variable changed per test
- [ ] Results documented and shared

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## Key Takeaways

1. **CRO is a process, not a project** - Continuous testing, learning, optimization
2. **Data beats opinions** - Always test assumptions; never rely solely on best practices
3. **User-centric thinking wins** - Understand needs, motivations, pain points
4. **Small changes compound** - 10% improvements across 10 elements = 2.6x overall lift
5. **Mobile matters** - Optimize mobile separately; fundamentally different experience
6. **Copy is king** - Words matter more than most people think
7. **Trust drives conversions** - Social proof, guarantees, transparency reduce friction
8. **Personalization amplifies** - Relevant experiences convert better than generic ones

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## Tools Referenced

- **Analytics:** Google Analytics, Adobe Analytics, Matomo, Mixpanel, Amplitude, Heap
- **Behavioral:** Hotjar, Crazy Egg, FullStory, Lucky Orange
- **Testing:** Optimizely, VWO, Google Optimize, AB Tasty
- **Surveys:** Qualaroo, SurveyMonkey, Typeform
- **User Testing:** UserTesting.com, UsabilityHub, Maze
