---

name: marketing-cro description: Conversion Rate Optimization - A/B testing methodology, landing page optimization, form design, statistical significance, and funnel analysis.

CRO — CONVERSION OPTIMIZATION OS (OPERATIONAL)

Built as a no-fluff execution skill for systematic conversion rate optimization.

Structure: Core CRO fundamentals first. Advanced testing in dedicated sections. AI/ML optimization in clearly labeled "Optional: AI / Automation" sections.

---

Modern Best Practices (January 2026)

• Google Optimize sunset: Use VWO, Optimizely, or PostHog
• Statistical significance: https://www.evanmiller.org/ab-testing/
• CXL Institute: https://cxl.com/
• Baymard Institute UX: https://baymard.com/

---

When to Use This Skill

• Landing page optimization: Hero, CTA, proof, form optimization
• A/B testing: Hypothesis design, sample size, statistical significance
• Funnel analysis: Drop-off identification, micro-conversion mapping
• Form optimization: Field reduction, multi-step forms, friction removal
• Trust/credibility: Social proof, security signals, guarantees

---

Core: CRO Framework

The CRO Process

1. ANALYZE → Identify conversion problems (data + qualitative)
2. HYPOTHESIZE → Form testable hypotheses
3. PRIORITIZE → Score by impact/effort (ICE/PIE)
4. TEST → Run A/B tests with statistical rigor
5. LEARN → Document results, iterate
6. IMPLEMENT → Roll out winners, test next

Conversion Rate Benchmarks

Page Type	Poor	Average	Good	Great
Landing page	<1%	2-3%	4-5%	>6%
Checkout	<40%	50-60%	65-75%	>80%
Form completion	<20%	30-40%	45-55%	>60%
Add to cart	<3%	5-8%	9-12%	>15%

Note: Benchmarks vary significantly by industry. Use as directional only.

---

Core: Landing Page Optimization

Above-the-Fold Checklist

Every landing page needs these elements visible without scrolling:

Element	Requirement	Common Issues
Headline	Clear value proposition	Vague, company-focused
Subheadline	Specific benefit or outcome	Missing or weak
Hero image/video	Relevant, shows outcome	Stock photos, irrelevant
CTA	Prominent, action-oriented	Hidden, generic text
Trust signal	Logo strip, rating, or stat	Missing entirely

Headline Formula

[Outcome] + [Timeframe/Ease] + [Without Pain Point]

Examples:
"Get 10 qualified leads per week without cold calling"
"File your tax return in 15 minutes with expert review"
"Double your email conversions without hiring a copywriter"

CTA Button Best Practices

Do	Don't
"Start Free Trial"	"Submit"
"Get My Quote"	"Click Here"
"Book My Demo"	"Learn More" (bottom of funnel)
"Download the Guide"	"Send"

CTA Button Optimization:

• Size: Large enough to tap on mobile (min 44px height)
• Color: Contrasts with page background
• Position: Above fold AND after key sections
• Text: First person ("Get My...") often outperforms second person

Trust Elements Hierarchy

STRONGEST TRUST SIGNALS (use at least 3):
├─ Customer logos (recognizable brands)
├─ Review score (4.5+ stars with count)
├─ Security badges (SSL, payment, compliance)
├─ Money-back guarantee
└─ Phone number visible

SUPPORTING TRUST SIGNALS:
├─ Customer testimonials (with photo, name, company)
├─ Case study snippets (specific metrics)
├─ "As seen in" media logos
├─ Team photos (for services)
├─ Live chat widget
└─ Physical address (for services)

---

Core: Form Optimization

Form Field Rules

Rule	Why	Impact
Minimum fields	Every field = friction	-10% CVR per field (approx)
Email first	Captures partial submissions	+15-30% lead capture
Labels above fields	Faster scanning	+10% completion
Single column	Easier flow	+5-10% completion
Inline validation	Catch errors early	+22% completion

Field Priority (Ask Only What You Need)

Priority	Field	When Required
1	Email	Always
2	Name	If personalization needed
3	Company	B2B only
4	Phone	Sales-ready leads only
5	Job title	Enterprise targeting
6+	Everything else	Gate behind progressive profiling

Multi-Step Form Pattern

Step 1: Low commitment (email)
├─ "What's your email?"
├─ Progress indicator: 1 of 3
└─ CTA: "Continue"

Step 2: Qualifying info
├─ Company size / Industry
├─ Progress indicator: 2 of 3
└─ CTA: "Almost there"

Step 3: Contact info
├─ Name / Phone (optional)
├─ Progress indicator: 3 of 3
└─ CTA: "Get My [Deliverable]"

Multi-step benefits:

• Commitment and consistency principle
• Captures partial data (even if abandoned)
• Feels less overwhelming
• Can qualify leads progressively

---

Core: A/B Testing Methodology

Hypothesis Template

IF we [change/add/remove X]
THEN [metric] will [increase/decrease] by [estimate]
BECAUSE [reasoning based on data/research]

Example:
IF we add customer logos to the hero section
THEN form conversion will increase by 15%
BECAUSE trust signals reduce perceived risk for new visitors

Sample Size Calculator

Minimum sample size formula (simplified):

n = (16 × p × (1-p)) / MDE²

Where:
- n = sample per variant
- p = baseline conversion rate
- MDE = minimum detectable effect (e.g., 0.10 for 10% lift)

Example:
Baseline CVR: 3% (0.03)
MDE: 20% relative lift (looking for 3.6% or higher)

n = (16 × 0.03 × 0.97) / (0.006)²
n ≈ 12,933 per variant

Total traffic needed: ~26,000 visitors

Quick reference:

Baseline CVR	10% MDE	20% MDE	30% MDE
1%	63,000	15,800	7,000
3%	20,700	5,200	2,300
5%	12,200	3,050	1,350
10%	5,800	1,450	650

Per variant. Multiply by 2 for total traffic needed.

Statistical Significance

Requirements for valid test:

• 95% confidence level (minimum)
• Run for at least 1-2 full business cycles (7-14 days)
• Don't peek and stop early (increases false positives)
• Document before test: hypothesis, primary metric, sample size, duration

Test Prioritization: ICE Framework

Factor	Score (1-10)	Description
Impact		How much will this move the metric?
Confidence		How sure are we this will work?
Ease		How easy is this to implement?
ICE Score		(Impact + Confidence + Ease) / 3

ICE Score interpretation:

• 8-10: High priority, test immediately
• 5-7: Medium priority, add to queue
• 1-4: Low priority, revisit later or skip

---

Core: Funnel Analysis

Funnel Diagnostic Framework

STEP 1: Map your funnel
Page Visit → Key Action → Form Start → Form Complete → Confirmation

STEP 2: Measure drop-off at each step
├─ Page Visit to Key Action: ___% (bounce rate inverse)
├─ Key Action to Form Start: ___%
├─ Form Start to Complete: ___%
└─ Complete to Confirmation: ___%

STEP 3: Identify biggest drop-off
Biggest percentage drop = highest priority to fix

STEP 4: Diagnose root cause
├─ High bounce? → Relevance, load speed, messaging
├─ Low engagement? → Content, CTA visibility
├─ Form abandonment? → Form friction, trust
└─ Checkout drop? → Pricing, shipping, trust

Micro-Conversion Mapping

Funnel Stage	Micro-Conversions to Track
Awareness	Scroll depth, time on page, video views
Interest	CTA hover, tab/section views, resource clicks
Consideration	Pricing page visit, comparison page, demo video
Decision	Form start, add to cart, checkout start
Conversion	Form complete, purchase, signup

Heatmap & Recording Analysis

What to look for:

• Click heatmaps: Are users clicking CTAs? Clicking non-clickable elements?
• Scroll maps: Where do users stop scrolling? Key content below fold?
• Session recordings: Where do users hesitate? Rage clicks? Form confusion?
• Form analytics: Which fields cause abandonment? Error patterns?

---

Core: Page Speed Optimization

Speed Impact on Conversion

Load Time	Impact
0-2 seconds	Baseline (optimal)
3 seconds	-7% conversion
5 seconds	-22% conversion
10 seconds	-50%+ conversion

Source: Google/Akamai research, directional only

Core Web Vitals Targets

Metric	Good	Needs Improvement	Poor
LCP (Largest Contentful Paint)	<2.5s	2.5-4s	>4s
INP (Interaction to Next Paint)	<200ms	200-500ms	>500ms
CLS (Cumulative Layout Shift)	<0.1	0.1-0.25	>0.25

Quick Speed Wins

Action	Impact	Effort
Compress images	High	Low
Enable caching	High	Low
Remove unused scripts	Medium	Medium
Lazy load below-fold content	Medium	Low
Use CDN	High	Medium
Optimize fonts	Medium	Low

---

Quick Reference

Task	Template	Location
Landing page audit	Page audit checklist	templates/landing-audit.md
A/B test plan	Test hypothesis doc	templates/ab-test-plan.md
Form audit	Form optimization	templates/form-audit.md
Funnel analysis	Funnel diagnostic	templates/funnel-analysis.md
Test prioritization	ICE scoring matrix	templates/ice-scoring.md

---

Decision Tree (CRO Triage)

Low conversion rate?
├─ Check page speed first (if >3s, fix that)
├─ Check bounce rate
│   ├─ High bounce (>70%) → Message/audience mismatch
│   └─ Normal bounce → Continue diagnosis
├─ Check scroll depth
│   ├─ Low scroll → Above-fold problem
│   └─ Good scroll → Below-fold CTA/proof issue
├─ Check form analytics
│   ├─ Low form starts → CTA/offer problem
│   └─ High abandonment → Form friction
└─ Check mobile vs desktop
    ├─ Mobile worse → Mobile UX issues
    └─ Same → Universal issue

Form abandonment?
├─ Check which field causes drop-off
├─ Reduce fields to minimum
├─ Add progress indicator
├─ Add inline validation
└─ Test multi-step

Traffic but no clicks?
├─ CTA not visible → Move above fold
├─ CTA not compelling → Test copy
├─ Too many options → Simplify, single CTA
└─ Page too long → Add sticky CTA

---

Operational SOPs

Weekly CRO Review (30 minutes)

1. Check conversion metrics

   • Landing page CVR vs last week
   • Form completion rate
   • Funnel stage conversion rates

2. Review active tests

   • Current test status
   • Statistical significance check
   • Call winner if significant

3. Prioritize next tests

   • Score new ideas (ICE)
   • Plan next week's tests
   • Document learnings

Monthly CRO Audit (2 hours)

1. Full funnel analysis

   • Map all conversion points
   • Identify top 3 drop-off points
   • Quantify opportunity (traffic × CVR gap)

2. Heatmap/recording review

   • Review 10-20 session recordings
   • Analyze click and scroll heatmaps
   • Document friction points

3. Test performance review

   • Win/loss ratio
   • Cumulative lift from tests
   • Update testing roadmap

4. Competitive analysis

   • Review competitor landing pages
   • Note new patterns/trends
   • Identify test ideas

---

Templates

Template	Purpose
landing-audit.md	Full landing page audit
ab-test-plan.md	A/B test planning
form-audit.md	Form optimization checklist
funnel-analysis.md	Funnel diagnostic
ice-scoring.md	Test prioritization

---

Anti-Patterns

Anti-Pattern	Why It Fails	Instead
Testing too small changes	Undetectable effect, wasted time	Test big, obvious changes first
Stopping tests early	False positives, bad decisions	Run to calculated sample size
No hypothesis	Random changes, no learnings	Document hypothesis before test
Testing everything at once	Can't isolate what worked	One variable at a time
Ignoring mobile	60%+ traffic is mobile	Mobile-first optimization
Copying competitors	Different audience, context	Use for ideas, test your own
Only A/B testing	Misses qualitative insights	Combine with user research

---

Optional: AI / Automation

Note: Core CRO fundamentals above work without AI. This section covers optional AI capabilities.

AI-Powered CRO Tools

Tool Type	Use Case	Examples
AI copy generation	Headline/CTA variants	Claude, GPT, Jasper
Personalization	Dynamic content by segment	Optimizely, VWO
Predictive testing	Predict winners faster	Evolv AI, Sentient
Auto-optimization	Multi-armed bandit	Google Optimize (sunset), VWO

When to Use AI

HAVE thousands of daily conversions?
├─ YES → AI personalization can optimize in real-time
└─ NO → Stick to traditional A/B testing

NEED many variants quickly?
├─ YES → AI copy generation for variant ideation
└─ NO → Human copywriting with hypothesis

HAVE limited traffic?
├─ YES → Qualitative research over testing
└─ NO → Statistical A/B tests

---

Related Skills

• marketing-leads-generation — Lead capture strategies
• marketing-paid-advertising — Traffic sources
• marketing-seo-technical — Page speed, Core Web Vitals
• software-ui-ux-design — Design patterns
• software-ux-research — User research methods

---

Usage Notes (Claude)

• Stay operational: return checklists, audit results, test plans
• Always include statistical significance requirements for testing
• Recommend qualitative research for low-traffic sites
• Use benchmark ranges, not absolute numbers
• Do not invent conversion data; state "varies by industry" when uncertain