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ACOS vs TACOS: Which One Actually Tells You If Your Book Business Is Profitable
ACOS divides your ad spend by the retail sale price Amazon credits to your ads — money you never keep. TACOS divides it by the royalties your ads actually generated. Here is the difference, a worked example, how to read TACOS (100% is break-even), and why it is the only ad metric denominated in money you keep.
Amazon Best Sellers Rank Explained: What Your BSR Actually Means in Sales
BSR is a position in a race, not a sales counter — recalculated hourly, decaying without sales, separate for every format and every marketplace. Here is how the rank really works, roughly what different BSR levels mean in daily sales, and the mistakes authors make reading it.
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Amazon Ads for KDP Beginners: A First Campaign That Won't Burn Your Budget
Your first Amazon ad campaign, step by step: which campaign type to start with, how to set bids and budgets that can't hurt you, the two-campaign structure that harvests keywords automatically, and — the part every tutorial skips — how to know if it's actually making money.
KDP No Sales? A 10-Point Diagnostic That Finds the Actual Problem
Zero sales has exactly two possible causes: nobody sees the book, or people see it and don't buy. Here is a 10-point checklist that tells you which one you have — visibility or conversion — and what fixes each, before you spend a cent on ads.
KDP Royalty Rates Explained: 35% vs 70%, and What Amazon Actually Pays You
The 70% royalty option is not automatic and not always the better deal. Here is exactly how KDP's 35% and 70% ebook tiers work, what the delivery fee really costs, how paperback and hardcover royalties are computed, and the pricing traps that quietly cut your royalty in half.
KDP Taxes for Non-US Authors: Withholding, the Tax Interview, and the 30% You Might Be Losing
By default, Amazon withholds 30% of your US royalties if you are not a US person — and a five-minute tax interview with the right treaty claim can cut that to 0% for many countries. Here is how KDP withholding actually works, what the W-8BEN does, and the mistakes that quietly cost authors thousands.
Break-Even ACOS: The One Number That Decides If Your KDP Ads Make Money
Break-even ACOS is the exact point where an Amazon ad stops costing you money. Here is the formula, worked examples for ebooks and paperbacks, and why comparing ACOS to your list price is the mistake quietly draining your budget.
Stop Burning Money: Finding Wasted Ad Spend in Your Amazon Book Campaigns
Unmanaged Amazon book campaigns waste 30–50% of their budget on clicks that never convert. Here is how to read your search-term report, concrete rules for negative keywords, and why waste should be measured against net profit.
How Much Do Amazon KDP Ads Cost? Real Budgets for Authors, From $5/Day Up
Amazon ads have no minimum spend and no fixed price — you pay per click, at auction. Here is what book clicks typically cost, what a $5, $10 and $20 daily budget realistically buys, how to size a budget from your royalty instead of a round number, and when raising the budget is the wrong move.
KDP Ads Not Delivering? Why Your Campaign Gets No Impressions, and the Fix Ladder
An Amazon ad campaign with zero impressions isn't broken — it's losing auctions. Here is the diagnostic ladder, in order: bid, relevance, targeting width, and the 'low search volume' trap, plus what a healthy ramp-up actually looks like so you stop fixing campaigns that just needed 48 hours.
One Book, Seven Currencies: Tracking KDP Profit Across US, UK, DE, FR, ES, IT & JP
The same book can be profitable in the US and lose money in Germany once ad VAT, withholding tax, and currency conversion are counted. Here is why you can't just add up numbers from different dashboards — and what a consolidated, tax-aware P&L should look like.
Is KDP Select Worth It? Kindle Unlimited Exclusivity, Decided With Data
KDP Select trades ebook exclusivity for Kindle Unlimited page reads, promo tools and 70% royalties in four extra marketplaces. Whether that trade wins depends on your genre's read-through economics — not on ideology. Here is what Select actually grants, what it actually costs, and the numbers that settle it.
KENP Explained: How Kindle Unlimited Page Reads Become Royalties
Kindle Unlimited doesn't pay per borrow — it pays per normalized page read, at a rate Amazon derives each month from a global fund and only announces mid-following-month. Here is how KENPC works, what a page read is actually worth per marketplace, and how to compute what your reads really earn.
Your ACOS Is Lying: How Kindle Unlimited (KENP) Hides Your Real Ad Profit
When a Kindle Unlimited reader clicks your ad and borrows your book, Amazon records the spend but zero revenue — so your ACOS looks awful even when you made money. Here is how KENP page-read royalties change the math, and how TACOS folds them into the royalties your ads actually generated.
Net Profit Per Book: How to Know Which Titles Actually Make You Money
An account-level ACOS hides the losing titles your winners are subsidising. Here is how to calculate net profit per book, the costs authors forget, and a simple framework for deciding what to scale, fix, or pause.
Realistic KDP Earnings: What Authors Actually Make (and the Math Behind It)
Screenshots of five-figure months tell you nothing about what KDP realistically pays. Here is the honest math: what one book earns at realistic sales volumes, why gross royalty screenshots hide the ad spend behind them, and the three levers that actually move author income.
KDP Reports Explained: Dashboard, Royalties Estimator, Orders — and Which Numbers to Trust
The KDP dashboard, the Royalties Estimator, the Orders report and the Payments report update at different speeds and measure different things — which is why they never quite agree. Here is what each report actually contains, how fresh each number really is, and the one that finally settles what you earned.
When Does Amazon KDP Pay You? The 60-Day Cycle, Thresholds, and Why a Payment Is 'Missing'
KDP pays royalties roughly 60 days after the end of the month they were earned — per marketplace, per currency, and only above certain thresholds for some payment methods. Here is the full payment timeline, what actually delays a payment, and a checklist for the classic 'why hasn't KDP paid me' panic.