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Break-even ACOS calculator

Break-even ACOS equals your pre-ad profit margin. Run campaigns above it and every advertised sale loses money — know your number before you set bids.

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Break-Even ACOS Calculator

ACOS is ad spend ÷ ad-attributed sales. Your break-even ACOS is simply your profit margin before advertising — spend above it and each advertised sale loses money. Set a target net margin to get the ACOS and max CPC that protect it.

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How the break-even ACOS calculator works

Price minus fees minus product cost is your pre-ad profit; divided by price it is your break-even ACOS. Subtracting the net margin you want to keep gives your target ACOS. Multiplying price × ACOS × conversion rate turns either number into the maximum you can pay per click, which is what you actually set in the campaign.

Frequently asked questions

What is a good ACOS on Amazon?

There is no universal number — it depends entirely on your margin. A 40% ACOS is fine for a product with a 55% pre-ad margin and disastrous for one with 25%. Compare against your own break-even, not a benchmark.

What is the difference between ACOS and TACoS?

ACOS divides ad spend by ad-attributed sales only; TACoS divides it by total sales including organic. TACoS falling over time while sales grow is the sign ads are building organic rank.

Why does my target ACOS come out negative?

Your requested net margin is larger than your pre-ad margin, so ads cannot be profitable at that price. Raise the price, cut costs, or accept a smaller net margin.

All free seller calculators

Amazon

All Amazon →

Everything Amazon takes from a sale, worked out from the official 2026 US rate card: referral and FBA fulfilment fees, size tiers, storage, and the ACOS ceiling your ads can afford.

Amazon FBAReferral, fulfillment & storage fees from the official 2026 rate card, with auto size-tier detection.Break-Even ACOSBreak-even ACOS, target ACOS for your desired net margin, and maximum cost-per-click.Size Tier CheckerYour 2026 Amazon size tier, dimensional weight, and exactly what to shrink to drop a tier.Amazon FBA UKAmazon UK referral, fulfilment by size band, storage and VAT in GBP — profit, margin, ROI and break-even.Amazon FBA EU (DE)Amazon EU (DE) referral, fulfilment by size band, storage and VAT in EUR — profit, margin, ROI and break-even.Amazon FBA CanadaAmazon Canada referral, fulfilment by size band, storage and GST/HST in CAD — profit, margin, ROI and break-even.Amazon FBA AustraliaAmazon Australia referral, fulfilment by size band, storage and GST in AUD — profit, margin, ROI and break-even.Amazon FBA IndiaAmazon India referral, fulfilment by size band, storage and GST in INR — profit, margin, ROI and break-even.Amazon FBA JapanAmazon Japan referral, fulfilment by size band, storage and Consumption tax in JPY — profit, margin, ROI and break-even.

Marketplaces

All Marketplaces →

Each marketplace stacks fees differently — on shipping, per order, per listing, or through ads. Pick your channel and see what one order really nets you.

eBay13.6% final value fee on item + shipping, automatic $0.30/$0.40 per-order tier, Promoted Listings.Walmart8–15% referral by category, WFS fulfillment, ROI and break-even price.EtsyListing + 6.5% transaction + payment processing, with US and UK presets and Offsite Ads.TikTok Shop8% referral fee plus creator affiliate commission — see your real payout per order.Shopify / PayPalShopify Payments, Stripe or PayPal processing plus your monthly platform bill spread per order.

Pricing & Profit

All Pricing & Profit →

Channel-independent maths every seller needs: what a unit truly costs to land, what margin a price leaves, and what price a target margin requires.

Landed CostFreight, duty & tariffs turned into the true per-unit cost behind every pricing decision.Reverse PricingStart from your target margin and get the exact price to charge — % fees handled correctly.Margin & MarkupMargin vs markup for any product in any currency, plus target-margin pricing mode.
Amazon changes fees every January.
Get one email when the rate card changes — no spam, just the update.
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