Amazon Ads put your book in front of readers who are already shopping for books in your genre. Unlike social media advertising where you interrupt people's feed, Amazon Ads appear at the moment of purchase intent, someone is on Amazon, searching for their next read, and your book shows up as an option. That fundamental difference is why Amazon Ads have become the primary paid marketing channel for indie authors, with an estimated 68% of self-published authors running at least one campaign in 2025.
Here's how to start without burning through your budget learning expensive lessons.
Understanding Amazon Ad Types
Amazon offers three ad formats for KDP authors. Each works differently and serves a different purpose.
Sponsored Products
This is where you start. Sponsored Products ads place your book cover in search results and on other books' product pages. They look almost identical to organic results, with a small "Sponsored" label.
How they work:
- You bid on keywords (e.g., "cozy mystery") or target specific books/categories
- When a reader searches for your keyword, your ad competes in an auction
- If you win the auction, your ad is displayed
- You pay only when someone clicks your ad (CPC, cost per click)
- Clicking the ad takes the reader to your product page
Why start here: Sponsored Products are the simplest ad type, have the lowest barrier to entry, and provide the most actionable data for beginners. You can launch a campaign in 10 minutes.
Sponsored Brands
Sponsored Brands ads display a banner at the top of search results featuring your author name, a custom headline, and up to three book covers. They're available once you have three or more books.
Best for:
- Series promotion (show books 1-3 in reading order)
- Brand building (establish your author name with genre readers)
- High-visibility placements (top of search results page)
Trade-offs: Higher cost per click (typically 1.5-2x Sponsored Products), require more creative effort, and need a catalog of at least three books.
Lock Screen Ads
Lock Screen Ads appear as display ads on Kindle e-readers (the ad-supported, lower-priced models). They use interest-based targeting rather than keyword targeting.
Best for:
- Reaching Kindle-native readers
- Wide audience awareness
- Lower CPCs (typically $0.15-$0.40)
Trade-offs: No keyword targeting means less precision. You target by interest categories (e.g., "Romance Readers") rather than specific search queries. Harder to measure direct impact on sales.
Ad Type Comparison
| Feature | Sponsored Products | Sponsored Brands | Lock Screen Ads |
|---|---|---|---|
| Placement | Search results, product pages | Top of search results | Kindle e-reader lock screens |
| Targeting | Keywords, products, categories | Keywords, products | Interest-based |
| Minimum books | 1 | 3 | 1 |
| Avg. CPC range | $0.25-$0.75 | $0.40-$1.20 | $0.15-$0.40 |
| Best for | Direct sales | Brand awareness, series | Broad reach |
| Recommended for beginners | Yes (start here) | After 3+ books | Optional |
Setting Up Your First Campaign
Follow these steps to launch a Sponsored Products campaign that generates useful data without wasting money.
Step 1: Choose Manual Targeting
Amazon offers "Automatic" and "Manual" targeting. Automatic lets Amazon decide which searches trigger your ad. Manual lets you choose specific keywords or products.
Start with Manual. Automatic targeting sounds easier, but it gives you less control and often wastes budget on irrelevant placements. You can always add an Automatic campaign later to discover new keywords, but your primary campaign should be Manual.
Step 2: Build Your Keyword List
Start with 50-100 keywords across three categories:
Genre keywords (30-40):
- "cozy mystery"
- "small town romance"
- "psychological thriller"
- "epic fantasy series"
- Your specific subgenre terms
Comp author keywords (15-25):
- Names of authors whose readers would enjoy your book
- Search for the top 20 authors in your subcategory
- Use first name + last name format
Theme/trope keywords (10-15):
- "enemies to lovers"
- "found family"
- "unreliable narrator"
- Specific tropes popular in your genre
Step 3: Set Your Bids and Budget
Daily budget: $5-$10 per campaign. This gives you enough data to optimize without significant financial risk. At $5/day, your maximum monthly spend is $150, a reasonable test budget.
Default bid: $0.35-$0.50 for most genres. Romance and thriller tend to be more competitive ($0.40-$0.65). Non-fiction and niche genres can start lower ($0.25-$0.40).
Match types:
- Exact match, your ad only shows for the exact phrase. Use for your top 10-15 keywords.
- Phrase match, your ad shows when the reader's search contains your phrase. Use for most keywords.
- Broad match, your ad shows for related searches. Avoid initially, it burns budget on irrelevant queries.
Step 4: Let It Run for 14 Days
Don't touch your campaign for the first two weeks. Amazon's attribution data has a 14-day lookback window, a click today might result in a sale 10 days from now. Optimizing before you have 14 days of data leads to bad decisions.
Understanding Key Metrics
ACoS (Advertising Cost of Sales)
ACoS is your most important metric. It tells you what percentage of your ad-generated revenue you're spending on ads.
Formula: ACoS = (Ad Spend / Ad Revenue) x 100
Example: You spent $50 on ads and generated $200 in attributed sales. ACoS = ($50 / $200) x 100 = 25%.
What ACoS Should You Target?
Your target ACoS depends on your royalty rate and strategy:
| Ebook Price | Royalty (70%) | Break-Even ACoS | Profitable ACoS Target |
|---|---|---|---|
| $2.99 | $2.09 | 100% | Under 70% |
| $3.99 | $2.79 | 100% | Under 70% |
| $4.99 | $3.49 | 100% | Under 70% |
| $6.99 | $4.89 | 100% | Under 60% |
| $9.99 | $6.99 | 100% | Under 50% |
Wait, how can break-even ACoS be 100%? Because ACoS measures the ratio of ad spend to revenue, and at 100% ACoS, you're spending exactly what you earn. But you still keep your royalty on organic (non-ad) sales, KU page reads, and future purchases from readers who discovered you through ads.
For series authors: An ACoS up to 100% on book 1 can be profitable if your series read-through is strong. If 50% of readers who buy book 1 also buy book 2, your effective revenue per reader acquired is much higher than a single sale.
Other Metrics to Monitor
Impressions, how many times your ad was displayed. Low impressions mean your bids are too low or your keywords aren't matching searches.
Clicks, how many readers clicked your ad. Clicks without sales usually indicate a cover, blurb, or price issue (not an ad issue).
CTR (Click-Through Rate), clicks divided by impressions. Industry average for book ads is 0.2-0.5%. Above 0.5% is strong. Below 0.15% suggests your cover isn't compelling enough for the audience your keywords are reaching.
Orders, confirmed sales attributed to your ad. Amazon's attribution window is 14 days.
Budget Planning: Realistic Scenarios
Here's what to expect at different budget levels over 90 days:
| Monthly Budget | Total 90-Day Spend | Expected Clicks (avg $0.40 CPC) | Expected Sales (3% conversion) | Revenue ($4.99 book) | Net Cost |
|---|---|---|---|---|---|
| $150 ($5/day) | $450 | 1,125 | 34 | $119 | -$331 |
| $300 ($10/day) | $900 | 2,250 | 68 | $237 | -$663 |
| $600 ($20/day) | $1,800 | 4,500 | 135 | $471 | -$1,329 |
These numbers look discouraging. But they only show direct ad ROI on a single book. The full picture includes:
- KU page reads from ad-acquired readers (often equal to 30-50% of direct sale revenue for KDP Select titles)
- Series read-through (book 1 buyer also buys books 2, 3, 4...)
- Organic sales lift, improved BSR from ad-driven sales leads to better organic visibility
- Also-bought placement, ad-driven sales build also-bought connections with comparable books
- Lifetime reader value, a reader who discovers you via ads may buy every future book
When you account for these factors, most indie authors who optimize their campaigns eventually reach profitability within 6-12 months.
Optimizing Your Campaigns
After your initial 14-day data collection period, start optimizing weekly.
Week 2-4: Identify Winners and Losers
Look at your search term report (available in the campaign manager under "Targeting"). This shows you exactly what readers searched for when they clicked your ad.
Action items:
- Keywords with sales, increase bids by 10-20% to win more auctions
- Keywords with clicks but no sales (20+ clicks), reduce bids by 25% or pause
- Keywords with zero impressions, increase bids by 30% or check relevance
- Irrelevant search terms, add as negative keywords to prevent future waste
Month 2-3: Refine and Scale
- Create a "Winners" campaign with only your profitable keywords at higher bids
- Launch a small Automatic campaign ($3/day) to discover new keyword opportunities
- Test different bid strategies: "Dynamic bids - down only" is safest for beginners
- Consider adding product targeting, target specific competitor books' product pages
Ongoing: The Optimization Cycle
Successful Amazon Ads are never "done." The most profitable indie authors spend 30-60 minutes weekly on:
- Reviewing search term reports and adding negatives
- Adjusting bids based on ACoS trends
- Pausing underperforming keywords
- Testing new keywords from autocomplete research and competitor analysis
- Adjusting budget allocation toward profitable campaigns
Common Beginner Mistakes
Mistake 1: Starting with Automatic Targeting Only
Automatic campaigns are useful for keyword discovery but terrible as your primary campaign. They show your ads for searches Amazon deems relevant, which often includes barely related queries that burn budget.
Mistake 2: Giving Up After Two Weeks
Amazon Ads are a marathon, not a sprint. The first 30-60 days are a learning investment. You're buying data about which keywords and audiences convert for your specific book. Authors who quit after two weeks of negative ROI miss the optimization phase where ads become profitable.
Mistake 3: Ignoring Conversion Rate
If you're getting impressions and clicks but no sales, the problem isn't your ads, it's your product page. Check your cover (is it genre-appropriate?), book description (does it hook readers?), reviews (do you have at least 10?), and price (is it competitive?).
Mistake 4: Setting Bids Too Low
Bids below $0.20 rarely win auctions in competitive genres. Your ads appear only when you win an auction, and if your bids are too low, you get zero impressions, meaning zero data to optimize from. Start at $0.35-$0.50 and adjust based on results.
Mistake 5: Not Tracking Full-Funnel Revenue
If you only look at direct ad revenue vs. ad spend, you'll almost always conclude ads aren't working. Include KU page reads, series sell-through, and organic sales lift in your calculations. Many authors find their total revenue increase exceeds their ad spend by 2-3x even when direct ACoS looks unprofitable.
When NOT to Advertise
Amazon Ads aren't right for every situation:
- Your book has zero reviews, Fix this first. Ads drive traffic to your page, but a page with no social proof converts poorly. Get 5-10 reviews before spending on ads.
- Your cover doesn't match genre expectations, Ads can't overcome a cover that signals the wrong genre. Invest in a professional cover before investing in ads.
- Your book file has quality issues, If Amazon has suppressed your book's visibility due to formatting or accessibility problems, ads will be less effective because your organic multiplier is reduced. Fix your EPUB formatting first.
- You can't commit to 90 days, A 2-week test isn't long enough to gather meaningful data. If your budget can't sustain 90 days at $5/day ($450 total), wait until it can.
For the complete picture of KDP strategy, including keywords, categories, pricing, and ranking factors that affect your ad performance, see our Amazon KDP Complete Guide.
Frequently Asked Questions
How much should I spend on Amazon Ads as a beginner?
Start with $5-$10 per day on a single Sponsored Products campaign. This gives you a maximum monthly spend of $150-$300 while generating enough data (clicks and impressions) to optimize effectively. Plan to spend at least $450-$900 over your first 90 days before evaluating whether ads are working for your book.
What's a good ACoS for book ads?
For most ebooks priced $2.99-$9.99, an ACoS under 70% is profitable on a single-book basis. For series starters, an ACoS up to 100% can be profitable when you factor in read-through to subsequent books. The "right" ACoS depends on your specific royalty rate, genre, and whether you're in KDP Select (where KU page reads add additional revenue per reader).
How long before Amazon Ads become profitable?
Most indie authors who actively optimize their campaigns report reaching profitability within 3-6 months. The first 30-60 days are typically a net loss as you gather data and identify winning keywords. Months 2-4 are the optimization phase where you cut waste and scale what works. By month 4-6, well-optimized campaigns are generating positive ROI for authors with strong covers, competitive books, and reasonable expectations.
Can I run Amazon Ads if I'm not in KDP Select?
Yes. Amazon Ads are available to all KDP authors regardless of KDP Select enrollment. Wide authors can run ads on Amazon while simultaneously selling on Apple Books, Kobo, and other platforms. The only difference is that KDP Select authors benefit from KU page read revenue on top of direct sales, which can improve overall ad profitability.
Should I use automatic or manual targeting?
Start with manual targeting. Choose 50-100 keywords relevant to your genre, comp authors, and tropes. After your manual campaign has been running for 30 days, add a small automatic campaign ($3/day) specifically to discover new keyword opportunities. Move any winning keywords from the automatic campaign into your manual campaign for better control over bids and budget allocation.