The Science Behind Amazon’s Exact Match Keywords: When Less Really Is More

The Precision Advantage in Amazon Advertising

In our work optimizing over $1.6 billion in ad spend, we’ve learned that the sellers chasing maximum impressions often generate the least profit. The campaigns that consistently deliver the highest returns focus on precision over volume.

Here’s what the data reveals: Well-managed Exact Match keywords deliver conversion rates 50-80% higher than Broad Match, with typical ACoS improvements of 20-35%. But these metrics only scratch the surface of what’s happening algorithmically.

Amazon’s A9 algorithm creates compound advantages for precision targeting. When Exact Match keywords drive consistent conversions, the A9 recognizes the relevance pattern. Quality Scores improve. CPCs trend downward. Organic rankings gradually climb. We see this progression repeatedly—focused targeting creates momentum that extends well beyond immediate sales.

Decoding Amazon’s Match Type System

The Three-Tier Targeting Framework

Amazon structures keyword targeting across three distinct match types, each serving a specific purpose in your campaign architecture:

Broad Match: The Discovery Tool

• Captures searches containing your keywords in any order
• Includes related terms, synonyms, and variations
• Example: “running shoes” matches “athletic footwear for jogging”
• Best for: Mining customer search language and discovering opportunities

Phrase Match: The Refinement Layer

• Requires your exact phrase in order, allows words before/after
• Example: “dog leash” matches “retractable dog leash” but not “leash for dogs”
• Best for: Testing specific phrases while maintaining flexibility

Exact Match: The Profit Driver

• Triggers only for your exact keyword or close variants
• Includes plurals, common misspellings, and minor variations
• Example: [coffee maker] matches “coffee maker,” “coffee makers,” and “coffe maker”
• Best for: Maximizing profitability on proven search terms

Understanding Close Variants on Amazon

Amazon’s interpretation of “close variants” for Exact Match includes:

• Singular/plural forms (“shoe” and “shoes”)
• Common misspellings (“cofee” for “coffee”)
• Punctuation differences (“dont” and “don’t”)

But explicitly excludes:

• Word reordering (“maker coffee” won’t match [coffee maker])
• Synonyms (“coffee brewer” won’t match [coffee maker])
• Additional words (“best coffee maker” won’t match [coffee maker])

This controlled flexibility helps capture real buyer intent while maintaining precision.

How Amazon’s A9 Algorithm Rewards Precision

Understanding Transactional Focus

Amazon’s A9 algorithm operates fundamentally differently from information-focused search engines. While Google optimizes for content relevance and user engagement, A9 has one primary directive: maximize purchase probability.

Core A9 Ranking Factors:

• Sales Velocity: Recent and historical sales performance
• Conversion Rate: Percentage of clicks resulting in purchases
• Keyword Relevance: Match between search terms and product attributes
• Click-Through Rate: Engagement with your listing in search results
• Price Competitiveness: Value proposition relative to alternatives
• Availability: Consistent in-stock status (FBA products get preference)
• Product Listing Quality: Completeness and optimization of content
• Customer Satisfaction: Reviews, ratings, and return rates

How Amazon’s Algorithm Interprets Match Type Signals

Amazon’s algorithm doesn’t just match keywords—it calculates purchase probability for every search-product combination. Exact Match keywords eliminate interpretive ambiguity.

Consider this scenario: A customer searches [stainless steel water bottle 32 oz]. When you target that exact phrase:

• The algorithm knows with high confidence your product matches their intent
• The A9 assigns maximum relevance weight
• Your ad competes primarily on performance metrics, not relevance guessing

This clarity creates algorithmic advantages:

• Higher Quality Scores from improved CTR (typically 0.8-1.2% vs 0.34% average)
• Preferential organic ranking consideration from consistent conversions
• Buy Box algorithm benefits from relevance signals
• Declining CPCs as A9 rewards performance

The Performance Feedback Loop

We’ve observed this pattern consistently:

1. Month 1: Exact Match keywords show higher CTR
2. Month 2: Improved Quality Score reduces CPCs by 10-20%
3. Month 3: Organic rankings begin improving for targeted terms
4. Month 4+: Reduced PPC dependency as organic traffic increases

One home goods brand experienced this firsthand: After concentrating 65% of budget on 30 Exact Match keywords, their average CPC dropped from $1.52 to $1.08 over four months. More importantly, organic sales for those keywords increased 40%, reducing overall advertising dependency.

Real Performance Metrics from the Field

ACoS: The Efficiency Reality

Based on aggregated client data from 2024:

• Broad Match ACoS: 28-38% (varies by category)
• Phrase Match ACoS: 20-30%
• Exact Match ACoS: 12-22%

Why such dramatic differences? Every Exact Match click represents someone who typed precisely what you’re selling. No exploratory shoppers. No comparison browsers. Just buyers with clear intent.

Conversion Rate: Where Profit Multiplies

Current Amazon benchmarks show:

• Platform Average: 9-10% (per Amazon’s reported data)
• Well-Optimized Exact Match: 15-20%
• Top Performers: 22-28% (typically brand + product combinations)

These aren’t incremental improvements. When conversion rates double, unit economics transform entirely. You can afford premium placement while maintaining healthy margins.

Cost Per Click: The Long-Term Advantage

Current average Amazon CPC: $1.04 (2025 data)

But here’s the pattern we see repeatedly:

• Initial Exact Match CPCs: 20-30% above Broad Match
• After 60 days: CPCs equalize due to Quality Score improvements
• After 120 days: Exact Match CPCs often 10-15% below Broad Match

This progression occurs because the A9 rewards relevance and performance over time.

The Eva Implementation Framework

Phase 1: Data Discovery (Days 1-30)

Never guess your Exact Match keywords. Let customers tell you:

1. Automatic Campaigns (25% of test budget)
   
   • Enable all targeting types
   • Set conservative bids
   • Mine search term reports every 48 hours
2. Broad Match Discovery (40% of test budget)
   
   • Target category-level terms
   • Use suggested bid minus 20%
   • Focus on impression share over efficiency
3. Documentation Discipline
   
   • Export search term reports bi-weekly
   • Highlight terms with 2+ conversions
   • Note exact customer phrasing (critical for Exact Match)

Phase 2: Strategic Keyword Graduation (Days 31-60)

Move proven performers to Exact Match campaigns:

Graduation Requirements:

• Minimum 3 conversions at profitable ACoS
• Consistent search volume (5+ searches weekly)
• Clear product-search alignment
• No brand confusion in search terms

Implementation Steps:

1. Create dedicated Exact Match campaigns
2. Set bids 25-35% above discovery campaigns
3. Add graduated terms as negative exact in source campaigns
4. Monitor hourly for first 48 hours (cannibalization check)

Phase 3: Single Keyword Ad Groups (Day 61+)

For keywords generating $500+ monthly revenue:

Campaign: [Brand] – Hero Products – Exact

  └── Ad Group: [bamboo cutting board] – EM

       └── Keyword: [bamboo cutting board]

       └── Initial Bid: $1.45

       └── Placement Adjustment: Top +60%

Why This Structure Works:

• Perfect performance attribution
• Granular bid optimization
• Clean A/B testing capability
• Maximum A9 relevance signals

Phase 4: Precision Negative Keywords

Even Exact Match campaigns need negatives. A9’s close variants can include unwanted variations:

Common Necessary Negatives:

• Accessories when selling main products
• Repair/replacement/parts variations
• Competitor brand combinations
• Different size/color specifications

Weekly review protocol: Check search terms, add negatives immediately, no exceptions.

Advanced Optimization for A9 Success

Dynamic Bidding Strategies by Keyword Age

New Exact Keywords (Days 1-14): Fixed bids only

• Establish clean baseline metrics
• Avoid algorithmic volatility
• Understand true conversion potential

Maturing Keywords (Days 15-60): Dynamic down only

• Protect against wasteful clicks
• Maintain stable ACoS
• Build performance history

Proven Performers (Day 61+): Dynamic up and down

• Maximize high-intent opportunities
• A9 optimization fully engaged
• Monitor for unusual spikes daily

Placement Optimization for Maximum A9 Impact

Your highest-converting keywords deserve premium visibility:

• Top of Search (Desktop): +50-80% adjustment
• Top of Search (Mobile): +40-60% (mobile converts differently)
• Product Pages: +20-40% for conquest campaigns
• Rest of Search: Base bid sufficient

Real data: A kitchen brand applied +70% Top of Search adjustment to their top 15 Exact Match keywords. Result: 52% sales increase with only 23% higher spend. Amazon’s algorithm rewarded the relevance with improved organic rankings within 90 days.

The Maximum Profitable Bid Formula

Calculate scientifically, not emotionally:

Maximum Bid = (Selling Price – COGS – Amazon Fees) × Target Profit % × Conversion Rate

Example:

• Selling Price: $40
• All-in Cost: $20
• Target Profit: 25% of revenue ($10)
• Exact Match Conversion Rate: 18%

Maximum Bid = $10 × 0.18 = $1.80

This ensures profitability even at full bid amount.

Common Failures and Field-Tested Solutions

“My Exact Match CPCs Are Killing Me”

Diagnosis: Usually targeting overly competitive terms.

Case Example: A pet supplies brand targeted [dog leash] at $2.80 CPC with 7% conversion. Research revealed customers actually searched [retractable dog leash 16 ft]. New CPC: $0.95. Conversion rate: 19%.

Solution: Mine your actual converting search terms. Don’t assume—verify through data.

“I’m Not Getting Enough Volume”

Reality Check: Exact Match isn’t about volume—it’s about profitable volume.

Case Example: A supplement brand generated “only” 400 orders/month from 40 Exact Match keywords. But those orders had 14% ACoS versus 32% for Broad Match. Profit per order was 3.5x higher.

Solution: Measure contribution margin, not vanity metrics. 100 profitable sales beat 1,000 break-even sales.

“The Algorithm Isn’t Improving My Organic Rankings”

Reality: The A9 requires sustained signals over time.

What We Typically See:

• Days 1-30: Improved paid placement only
• Days 31-90: Early organic movement (positions 20→15)
• Days 91-180: Significant improvement (positions 15→7)
• Day 180+: Stable top 10 positions for many keywords

Solution: Consistency over intensity. Maintain performance for 6+ months. Amazon’s algorithm is conservative—it wants proof of sustained relevance.

Strategic Portfolio Balance for Algorithmic Optimization

Structure your portfolio to feed A9’s algorithm:

Discovery Layer (20-30%):

• Automatic campaigns
• Broad match exploration
• New product launches
• Seasonal term testing

Refinement Layer (25-35%):

• Phrase match campaigns
• Emerging exact terms
• Competitor conquesting
• Category expansion

Profit Core (40-55%):

• Proven exact match keywords
• Brand defense terms
• High-LTV customer terms
• Top 20% performers

This structure evolves. New accounts might run 60% discovery initially. Mature accounts often operate at 65%+ Exact Match, feeding A9 consistent conversion signals.

Measuring Success Beyond Surface Metrics

Monthly Tracking Framework

Efficiency Indicators:

• Exact Match % of total sales
• Profit per order by match type
• TACoS trend (Total ACoS including organic)

A9 Algorithm Signals:

• Organic ranking movement for Exact keywords
• Search term impression share
• Buy Box win rate correlation

Business Health Metrics:

• Customer acquisition cost by source
• Repeat purchase rate by keyword type
• Review rate by traffic source

One electronics accessory brand discovered Exact Match customers had 35% higher lifetime value and left reviews at 2x the rate. A9 noticed too—their organic rankings improved across the board.

The Path Forward with A9

Exact Match mastery within the Amazon algorithm framework requires patience and precision. Start with systematic discovery. Graduate based on data, not assumptions. Optimize relentlessly. The sellers who commit to this process don’t just reduce ACoS—they build sustainable competitive moats that A9 reinforces over time.

At Eva, our AI analyzes millions of search term data points daily, identifying graduation opportunities and optimization potential human analysis might miss. But whether you’re optimizing manually or leveraging automation, the principle remains unchanged: A9 rewards precision that leads to purchases.

The marketplace belongs to sellers who understand this truth: your most profitable customers are searching for exactly what you sell. The question isn’t whether to prioritize Exact Match keywords—it’s how quickly you can identify and dominate the precise terms that matter to both your customers and A9’s algorithm.

Ready to get started? Book a free consultation today and let’s talk about how we can bring your e-commerce brand to the next levelI.

Frequently Asked Questions