Free Amazon KDP ACoS calculator
The KDP ACoS calculator is a free Amazon Ads tool that returns the break-even ACoS for a coloring book at a given list price and page count. It applies Amazon's cliff-aware royalty model (50% or 60% at the $9.99 line, minus print cost), so the break-even percentage is specific to your book, not a generic product margin.
Last updated: June 2026
Standard distribution royalty rate at this price: 60% (the $9.99 cliff is baked in).
106 interior pages (designs x 2 + 6 front matter, single-sided). Print cost: $2.30.
Net royalty per sale
$3.69
(60% x $9.99) - $2.30 print cost
Break-even ACoS
37%
Below this, an ad-driven sale profits. Above it, you pay to acquire the sale.
Net profit per ad-driven sale, by ACoS
What each ACoS level leaves after ad cost, sorted low to high. The break-even row (37%) is where profit crosses zero.
| ACoS | Band | Ad cost / sale | Net / sale | Verdict |
|---|---|---|---|---|
| 15% | Steady-state, efficient | $1.50 | $2.20 | Profit |
| 20% | Steady-state, typical | $2.00 | $1.70 | Profit |
| 25% | Steady-state, ceiling | $2.50 | $1.20 | Profit |
| 30% | Launch, efficient | $3.00 | $0.70 | Profit |
| 37% | Break-even (ad cost = royalty) | $3.69 | $0.00 | Break-even |
| 40% | Launch, typical | $4.00 | -$0.30 | Loss per sale |
| 50% | Launch, ceiling | $5.00 | -$1.30 | Loss per sale |
ACoS = ad spend / ad-attributed sales revenue. The launch band (30-50%) is the higher range most coloring books tolerate in months 1 to 3 to gather keyword-conversion data; the steady-state band (15-25%) is the efficient range once the book ranks. Any row above your break-even ACoS loses money on the ad-driven sale directly, but early launch spend can still pay off through the organic ranking lift that sales velocity buys.
What is a good ACoS for a KDP coloring book?
A good ACoS is any level materially below your break-even ACoS with stable conversion. For most coloring books, break-even sits between 35 and 45%, and a healthy steady-state campaign runs at 15 to 25%. Break-even depends on your specific royalty: a $9.99 book at the 60% rate breaks even around 37%, while a $7.99 book at the 50% rate breaks even lower because its per-sale royalty is thinner.
How is break-even ACoS calculated for a coloring book?
Break-even ACoS is net royalty per sale divided by list price. The royalty itself is the part most generic calculators get wrong: Amazon applies the royalty rate to the full list price, then subtracts the printing cost. At $9.99 with a 60% rate, that is (0.60 x $9.99) - $2.30 = $3.69 per sale. Dividing $3.69 by $9.99 gives a 37% break-even ACoS. This calculator runs that math with the same cliff-aware engine as the profit calculator.
Launch ACoS versus steady-state ACoS
The two phases call for different ACoS targets. In months 1 to 3, a launch campaign tolerates 30 to 50% ACoS to gather keyword-conversion data and build the sales velocity that lifts organic rank. Once the book ranks, the campaign should settle into a 15 to 25% steady-state band. The same break-even line applies to both phases, but during launch you accept short-term spend above it as an investment in ranking.
ACoS versus TACoS: which should you track?
ACoS measures only ad-attributed sales, so it tells you whether a campaign is efficient in isolation. TACoS (Total ACoS) divides ad spend by total sales, including organic, so it tells you whether ads are a healthy share of the whole business. A maturing book often shows a high ACoS but a falling TACoS, which is the signal that ads are seeding organic sales rather than carrying the book. Track ACoS per campaign and TACoS for the book overall.
ACoS interpretation reference
| ACoS band | What it means | Action |
|---|---|---|
| 15-25% | Efficient steady-state | Scale budget on the winning keywords |
| 26-35% | Profitable but watch it | Prune weak keywords, tighten match types |
| ~37% (break-even) | Ad cost equals royalty at $9.99 | Acceptable only for ranking during launch |
| 50%+ | Losing money per ad-driven sale | Cut bids or pause unless seeding launch rank |
Break-even shifts with your list price and page count. Enter your own numbers above for the exact figure.
Frequently asked questions
- What is ACoS in Amazon Ads?
- ACoS (Advertising Cost of Sales) is ad spend divided by ad-attributed sales revenue, shown as a percentage. An ACoS of 30% means you spent $30 in ads for every $100 of sales credited to those ads. It is the headline efficiency metric for Amazon Sponsored Products campaigns on KDP coloring books.
- What is a good ACoS for a KDP coloring book?
- Break-even ACoS for a coloring book is usually 35 to 45%, depending on list price and page count. At $9.99 with a 60% royalty and $2.30 print cost, break-even is about 37%. A healthy steady-state ACoS is 15 to 25%; anything materially under break-even with stable conversion is profitable.
- How do I calculate break-even ACoS?
- Break-even ACoS equals your net royalty per sale divided by your list price. Net royalty is (royalty rate times list price) minus printing cost. At $9.99, a 60% rate gives $5.99, minus a $2.30 print cost leaves $3.69. Divided by $9.99, that is a 37% break-even ACoS.
- Why do new ad campaigns start at a high ACoS?
- Amazon’s ad auction needs data to learn which keywords convert for your book. New campaigns typically run at 60 to 100%+ ACoS for the first 7 to 14 days. Let each keyword gather 30 to 50 clicks before pruning underperformers, rather than pausing on day-one ACoS.
- What is the difference between ACoS and TACoS?
- ACoS measures only ad-attributed sales. TACoS (Total ACoS) divides ad spend by total sales, including organic. A book with strong organic sales can show a high ACoS but a low TACoS, because ads are a small share of total revenue. TACoS is the better long-term health metric.
- Should I run ads at a loss during launch?
- Often yes, briefly. Spending above break-even ACoS loses money on each ad-driven sale directly, but the sales velocity can lift your organic Best Sellers Rank, which brings free sales later. Break-even is the per-sale line, not the campaign-success line. Keep launch overspend short and watch organic rank.
The break-even ACoS here is only as good as the royalty behind it. To project monthly and yearly revenue at a given price and sales velocity, use the profit calculator. To pick the list price in the first place, run the pricing wizard. For real per-sale royalty numbers, yearly earnings, and the full ad-margin breakdown across price points, see the profit margins guide. For the day-one ad-timing and launch-sequence playbook, see the launch day playbook. And for the term itself, see the ACoS glossary entry.
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Based on Amazon KDP's 2026 US marketplace pricing for black-ink paperbacks, standard distribution. Royalty = (rate x list price) - printing cost, with the rate at 50% under $9.99 and 60% at $9.99 or above. Print cost: $2.30 flat for 24-108 interior pages, $1.00 + $0.012/page for 110-828 pages. ACoS bands are directional guidance; verify against your live Amazon Ads reports.