Launching campaigns is 10% of the work. The other 90% is the weekly optimisation cycle that converts raw spend into compounding sales. Here is exactly what to do, in what order, and why — so your Amazon Ads improve every single week.
| 14-minute read | Intermediate · Advanced |
Amazon Ads optimisation is not a one-time task. It is a repeating weekly process that converts your ad spend into data, your data into decisions, and your decisions into progressively more efficient campaigns. Authors who launch and forget are paying for traffic that slowly degrades. Authors who run a disciplined weekly cycle are building a compounding advantage their competitors cannot catch up with.
This guide covers the full optimisation workflow — what to check, what to change, when to change it, and how to avoid the common mistakes that turn a profitable campaign into a money drain.
Why Most Authors Never Properly Optimise
There are two main reasons Amazon Ads accounts decay rather than improve over time. The first is that authors treat campaign launch as the finish line. They spend considerable effort setting up targeting, writing ad copy, and configuring bids — then check in weekly only to glance at spend and sales without making structured decisions. The account stagnates or slowly worsens as irrelevant searches accumulate unchecked.
The second reason is that authors lack a framework. The Amazon Ads console surfaces an overwhelming amount of data — impressions, clicks, spend, sales, ACoS, Search Term Reports — and without a clear order of operations, most of it becomes noise. Optimisation without a framework produces random, inconsistent changes that are just as likely to harm performance as improve it.
The solution is a weekly routine that takes roughly 30–45 minutes per book, follows a defined sequence, and makes decisions based on thresholds rather than intuition. After four to six weeks of consistent execution, almost every book’s advertising improves materially. After twelve weeks, the gap between an optimised account and an unoptimised one is typically measured in multiples, not percentages.
The Metrics That Matter and What They Tell You
Impressions tell you whether your ads are entering auctions. Very low impressions (under 500 per week for a new campaign) suggest bids are too low, targeting is too narrow, or metadata quality is limiting automatic campaign reach. Impressions alone tell you nothing about campaign quality — a campaign can have millions of impressions and be losing money at scale.
Click-through rate (CTR) measures how often someone who sees your ad clicks it. For books, a CTR of 0.3–0.6% is typical. Below 0.2% consistently suggests your ad creative (primarily your cover thumbnail and title as they appear in search results) is not compelling enough. Above 1.0% is excellent and usually indicates strong keyword relevance combined with an appealing cover. CTR is a cover and relevance signal, not a profitability signal — you can have a high CTR on irrelevant keywords and be losing money rapidly.
Conversion rate (CVR) measures how often a click becomes a sale. Book conversion rates vary enormously by genre, price, and review count. A book with 100+ reviews and a competitive price point in a high-intent genre might convert at 10–15%. A new book with few reviews might convert at 3–5%. What matters most is tracking your own book’s conversion rate as a baseline and watching for changes — a sudden drop in conversion often signals a price change, review decline, or listing issue rather than an advertising problem.
Advertising Cost of Sale (ACoS) is the core efficiency metric: ad spend divided by ad revenue, expressed as a percentage. An ACoS of 35% means you spent £0.35 in ads for every £1.00 in ad-attributed sales. Your target ACoS depends on your royalty margin — see the section below. ACoS tells you whether specific keywords, campaigns, or ad types are profitable, but it only counts sales Amazon attributes to that specific ad click.
Total Advertising Cost of Sale (TACoS) divides ad spend by total revenue — including organic sales. This is the truer measure of advertising’s overall impact on your business. A book with a TACoS of 12% is in very healthy shape: ads are driving growth without consuming the organic sales base.
Setting the Right ACoS Target for Your Book
Before you can judge whether a keyword or campaign is performing well, you need a break-even ACoS. The formula is simple: break-even ACoS = (royalty ÷ list price) × 100. A £4.99 Kindle book earning a 70% royalty generates a royalty of approximately £3.49 after delivery costs (using Amazon’s standard £0.10/MB delivery fee as a rough guide). Break-even ACoS = (£3.49 ÷ £4.99) × 100 = approximately 70%.
This means you can spend up to 70% of the sales price on ads before going into the red on ad-attributed sales. In practice, few authors target break-even — you want profitable ads, not break-even ads. A reasonable target ACoS for a direct-profit goal is 30–45% for most fiction and 20–35% for most non-fiction (where price points and royalties often differ). If you have a series, you may tolerate a higher ACoS on book one because readers who buy that book often go on to purchase the series — revenue your ad report never captures.
Set your target ACoS before you start optimising. It becomes the single threshold that determines whether a keyword is performing well (ACoS below target), marginally (at target), or poorly (above target). Without this number, all your optimisation decisions are relative to nothing.
The Weekly Optimisation Cycle
Run this sequence once per week, every week. On a new campaign (first two weeks), run it twice — at the end of week one and the end of week two — to catch early waste before it compounds. After week eight, you can sometimes extend to every ten days if campaigns are stable, but weekly is the default.
Step 1: Check the campaign summary. Look at the past seven days. Total spend, total attributed sales, overall ACoS. Is spend within your daily budget cap? If it hits the cap most days, you may need to increase budget (if the ACoS is good) or reduce bids (if ACoS is high). If it is nowhere near the cap, low bids or low relevance are limiting reach.
Step 2: Pull the Search Term Report. This is the most important action in any optimisation session. Filter for clicks ≥ 3 in the last seven days. Every term that has clicked and converted (sales > 0, ACoS ≤ target) goes onto a list for promotion to exact match in your manual campaign. Every term that has clicked with no sales (and has enough clicks to be statistically meaningful — usually 8–10 without a sale) goes onto a negative keyword list. Everything in between (1–7 clicks, no data yet) waits another week.
Step 3: Implement negatives. Add the confirmed waste terms as negative exact match to the automatic campaign where you found them. If the same terms appear in broad or phrase match manual campaigns, add them as negatives there too.
Step 4: Promote converters. Any search term that has produced 2+ sales in your automatic campaign at or below your target ACoS should be added as an exact match keyword to your manual exact match campaign. Set its opening bid at its current CPC (what you were paying in automatic) and watch it over the next two weeks. If it continues to convert well, you can test a modest bid increase. If it underperforms in manual, lower the bid — the manual environment is different from automatic because you are now bidding directly, not benefiting from Amazon’s auto-matching algorithm.
Step 5: Adjust bids on existing manual keywords. Sort your manual campaign keywords by ACoS. Keywords with ACoS significantly above target and 15+ clicks: lower bid by 15–20%. Keywords with ACoS significantly below target and stable click volume: test a bid increase of 10–15% to capture more of the available impression share. Keywords with zero clicks in 30 days: check whether bids are competitive (try raising by 25%) or consider pausing if raising does not produce clicks within two more weeks.
Step 6: Review budget allocation. Campaigns hitting budget caps on profitable keywords are leaving revenue on the table. Campaigns spending full budget at poor ACoS need budget reduction or bid cuts, not both simultaneously — change one variable at a time.
Mining the Search Term Report
The Search Term Report is the most valuable data source in your Amazon Ads account. It shows you the actual search queries — what real readers typed into Amazon — that triggered your ads. This is data Amazon does not make freely available anywhere else, and every click you pay for is buying you this intelligence.
Access it in the Amazon Ads console: navigate to Reports → Search Term Report, select your date range (seven to fourteen days is usually most actionable), and download. Filter the spreadsheet by clicks ≥ 3, then add a column calculating ACoS per term (ad spend ÷ attributed sales × 100 for any term with sales; mark as “no sale” for terms with zero sales).
Look for three categories: clear winners (low ACoS, multiple sales — promote these immediately), clear waste (multiple clicks, zero sales, clearly irrelevant — negate these immediately), and slow-burners (a few clicks, no sale yet — leave for another week unless the search term is obviously irrelevant). The middle category — queries that are relevant but have not yet converted — often just needs more data. Negating relevant search terms prematurely is one of the most common optimisation mistakes.
Over time, your Search Term Report becomes a map of your book’s market. After six to eight weeks of running automatic campaigns, you will have a rich, empirically validated keyword list for your manual campaigns — built entirely from reader behaviour rather than guess-work.
Adding Negative Keywords
Negative keywords block your ad from appearing for searches containing specified terms. Used correctly, they are one of the most effective tools for improving campaign efficiency — every irrelevant click you prevent saves you money and improves the signal-to-noise ratio in your data.
Use negative exact match for specific multi-word search terms that are clearly irrelevant: “free books,” “books for children,” “[genre you don’t write].” The negative exact match only blocks that precise phrase.
Use negative phrase match for root terms that are broadly irrelevant: adding “free” as a negative phrase blocks all searches containing the word free — useful for preventing budget waste on freebie hunters. Be careful with negative phrase match because it is broad: adding “romance” as a negative phrase in a campaign for a book with romantic elements would block many relevant searches.
Common negative keywords for fiction: “free,” “used,” “audiobook” (if you only have ebook/print), “large print,” author names of completely unrelated genres. Common negatives for non-fiction: “free pdf,” “download,” “free ebook,” unrelated subject matter. Build your negative list incrementally from Search Term Report data rather than adding a bulk list upfront — bulk pre-negatives often block terms you actually want.
Adjusting Bids by Keyword Performance
Bid adjustment is the most frequently executed optimisation action, and the most frequently done badly. Two rules prevent most bid-adjustment mistakes.
Rule 1: Change bids in small increments (10–20%) and wait at least 7–14 days before re-evaluating. Increasing a bid by £0.40 immediately after a single good week, then decreasing it by £0.50 after a single poor week, produces a bidding whipsaw that destroys any ability to read cause and effect. Each bid change creates a new auction environment. Give it time to settle before judging the outcome.
Rule 2: Use statistical significance thresholds. A keyword with 3 clicks and 0 sales is not statistically failing — it has insufficient data. A keyword with 25 clicks and 0 sales at £0.45 CPC (£11.25 in spend) for a £3.99 book with a £2.79 royalty is failing. The threshold question for pausing or drastically lowering a keyword bid is: have I spent more than my break-even royalty on this keyword with zero sales? If yes, intervention is justified. If no, wait.
When to Pause Keywords vs Lower Bids
Lower the bid when: the keyword is relevant (confirmed by search term data or your own knowledge) but ACoS is too high, suggesting the current bid is winning impressions you are overpaying for. A lower bid means you enter fewer auctions and pay less when you win — often enough to bring a marginally unprofitable keyword to profitability without losing meaningful volume.
Pause the keyword when: it has consistently shown 20+ clicks across multiple weeks with zero sales and the search terms it matches confirm irrelevance. A paused keyword can be re-activated at any time — pausing is not permanent, and it stops waste while preserving the keyword for future re-testing if conditions change (new reviews, price change, cover refresh).
Never delete keywords. Deleting removes the historical performance data. Pausing preserves it. The data on why something did not work is as valuable as the data on what does.
Keeping Campaign Structure Clean
Over time, campaigns accumulate keywords, ad groups, and negatives. A clean structure makes optimisation faster and prevents inter-campaign keyword cannibalisation (where your own campaigns compete against each other in auctions, driving up your costs).
Standard structure for a single book: one automatic campaign (all four sub-types running) generating discovery data; one manual exact match campaign running your proven converters; one manual broad/phrase campaign for mid-funnel exploration; optionally one Sponsored Brands campaign once you have three or more titles. Keep each purpose in a separate campaign — do not mix automatic and manual targeting in the same campaign.
If you are running multiple campaigns for the same book, add the book’s keywords as negative exact matches in the automatic campaign to prevent it from competing with your manual campaign on the same proven terms. This forces Amazon’s automatic system to keep exploring new search territory rather than repeatedly winning auctions for terms your manual campaign already owns efficiently.
Using Placement Bid Modifiers
Amazon Ads allows you to increase your bid by a percentage for three specific placement types: Top of Search (first row of results), Rest of Search (below the fold), and Product Pages (on ASIN detail pages). This is separate from your keyword bid — it is a multiplier on top of it.
To check whether a placement modifier is worth using, look at your Placement Report (Reports → Campaign Placement Report). If Top of Search shows a dramatically better conversion rate than Rest of Search or Product Pages, increasing your bid modifier for Top of Search — even by 25–50% — can concentrate more of your budget on the placement that converts best. If there is no meaningful difference, modifiers add complexity without benefit.
A common pattern: books with strong covers and clear genre signals often convert better at Top of Search because readers in active search mode self-select. Books with weak review counts sometimes convert better on Product Pages because readers encountering them while browsing a competitor’s also-bought section are in a more exploratory mindset. Check your own data before applying blanket modifiers.
Budget and Dayparting Considerations
Amazon Ads does not natively support dayparting (scheduling ads to run only during certain hours). Your daily budget is distributed by Amazon across the day using its own pacing algorithm. If your budget is consistently exhausted by early afternoon, Amazon’s algorithm is front-loading your spend into high-competition morning hours.
The practical response is either to increase daily budget (if ACoS is good) or to lower bids across all keywords by 10–15% to reduce spend velocity — letting your budget last through the full day rather than front-loading into the most expensive auctions. Some authors running particularly tight budgets find that lowering bids produces similar or better results at lower cost because they avoid the highest-competition auction windows.
Reading Campaign Reports Correctly
The 90-day view shows you trends. The 30-day view shows you current performance. The 7-day view shows you recent shifts. Use all three: the 90-day view tells you whether your campaigns are trending in the right direction; the 30-day view is your standard performance benchmark; the 7-day view helps you catch sudden changes quickly — a price change, a cover update, a review spike, or a competitor launching a heavy ad push in your category can all produce rapid changes visible only in the short window.
A critical reporting caveat: Amazon uses a 7-day attribution window for Sponsored Products (14 days for Sponsored Brands and Sponsored Display). This means a click today may not show the associated sale in your dashboard for up to seven days. The most recent five to seven days of data in your Sponsored Products report are always understated — sales have occurred but not yet been attributed. Do not make drastic bid cuts based on the most recent week’s data in isolation; always compare to older, fully-attributed periods.
Integrating ACoS and TACoS
ACoS only counts sales Amazon directly attributes to ad clicks. TACoS (total ad spend ÷ total revenue) incorporates organic sales, which are often lifted by advertising even when Amazon cannot directly attribute them. A well-run ad campaign typically raises a book’s BSR, which increases organic visibility, which drives organic sales — a flywheel effect that ACoS reporting completely misses.
If your ACoS is above your target but your TACoS is healthy (typically below 20% for most books), your ads are working at a business level even if the direct attribution looks marginal. Conversely, a good ACoS alongside a poor TACoS can indicate that ads are cannibalising organic sales rather than genuinely growing revenue. Track both, and optimise for TACoS as the primary measure of overall advertising health. See our dedicated TACoS guide for the full calculation and benchmarks.
Tools That Speed Up Optimisation
Manual optimisation from the Amazon Ads console and exported spreadsheets is effective but time-consuming. Several tools accelerate the workflow significantly. The Amazon Ads Generator in KDP Rank Fuel by Vappingo builds complete ad campaigns from your book’s metadata — including keyword lists with recommended match types, opening bids calibrated to your genre, and a negative keyword starter list — dramatically reducing the setup time before the first optimisation cycle begins. Combined with the Keyword Goldminer and Book Keyword Spy tools for building and validating your manual keyword lists, the research phase that typically takes several hours can be done in minutes.
The most important tool, however, is a consistent weekly calendar appointment. Fifteen minutes with a clear framework and the Search Term Report open will do more for your campaign performance than any software that removes you from the decision-making process. Use tools to accelerate data gathering; keep the decisions in your hands.
Clean, professional book listings also convert ad traffic more reliably. If your manuscript still needs proofreading before or after publication, Vappingo’s manuscript proofreading service ensures your book’s content is as strong as your advertising.
