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Amazon Seller Calculators

These are eleven free calculators for the decisions Amazon sellers actually make: what a unit really earns after the full fee stack, how much you can bid before advertising eats the margin, what a supplier quote costs once it lands, when to place the next purchase order, and what a deal or a return really costs. Each one runs entirely in your browser, stores nothing, and shows the formula in words so you can reproduce it in a spreadsheet. Every field loads with a worked example already filled in, so you can see the method before entering your own numbers.

Published August 31, 2026 · Last reviewed August 31, 2026 · These are estimators for planning. Confirm your own fees in Seller Central's Revenue Calculator and Fee Preview report before pricing, bidding, or ordering.

Profit and pricing

Start here. Nearly every other number on this page depends on knowing what one unit actually earns.

Inventory and cost

The cash side of the business: what inventory costs to land, to hold, to reorder, and to take back.

Advertising, testing, and fulfillment

The levers you pull weekly: bids, experiments, and how the product gets to the buyer.

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How to use these together

Each calculator answers one question, but they chain in a specific order, because the output of one is the input of the next:

  1. Establish your real cost. Run the landed cost calculator first. A supplier's ex-works quote is not what you pay, and every downstream number inherits this error if you skip it.
  2. Establish your real profit. Feed that landed cost into the FBA profit calculator along with your fees and blended advertising cost. This produces net profit per unit, margin, ROI, and the break-even price.
  3. Convert profit into advertising limits. Pre-ad profit sets your ceiling in the break-even ACoS calculator, and your conversion rate turns that ceiling into a bid in the max bid calculator.
  4. Check any promotion against the break-even price. Before scheduling a deal, run the deal impact calculator. Discounts that look modest often cross below break-even, where volume increases the loss.
  5. Plan the cash and the calendar. The reorder point and storage calculators decide how much to order and when, and the sourcing calculator gives you the price ceiling to negotiate against.

Worked example: one SKU through the chain

A single kitchen SKU selling at $24.99 with a 15% referral rate, a $6.10 fulfillment fee, $0.12 storage, and $2.90 blended advertising per unit. Figures are illustrative.

  • Landed cost: a $5.40 ex-works quote on a 2,000 unit order, with $3,200 freight, 12% duty, $450 in broker and insurance fees, $0.35 prep, and $600 inbound, lands at $8.52 per unit. The quote was 37% lower than the truth.
  • Profit: $24.99 − $8.52 − $3.75 referral − $6.10 − $0.12 − $2.90 = $3.60 per unit, a 14.4% net margin.
  • Advertising ceiling: pre-ad profit is $6.50, so break-even ACoS is 26.0%. At a 10% conversion rate, break-even cost per click is $0.65.
  • Break-even price: ($8.52 + $6.10 + $0.12 + $2.90) ÷ 0.85 = $20.75.
  • The deal test: a 20% coupon takes the price to $19.99, which is below that $20.75 floor. Every deal unit sells at a loss, so a bigger deal makes it worse, not better.

That last line is the point of running the chain rather than a single calculator: the promotion looked affordable against a 14.4% margin and was not.

Frequently asked questions

Are these Amazon seller calculators free?

Yes, all eleven are free with no account, signup, or usage limit. They are ordinary web pages, so you can bookmark any one of them and use it as often as you like.

Do these calculators store or transmit the numbers I enter?

No. Every calculation runs inside your own browser and nothing you type is sent anywhere, stored, or logged. This site has no backend to receive the data, which is why the calculators keep working with no network connection.

Which calculator should I start with?

Start with the FBA profit calculator, because almost every other number depends on knowing your true profit per unit. Once you have that figure, the break-even ACoS and maximum bid calculators turn it into advertising limits, and the sourcing calculator turns it into a supplier price ceiling.

Are the default fee values current Amazon rates?

No. Every field loads with an illustrative example so you can see the method working, not a live fee table. Replace the defaults with your own figures from the Fee Preview report and Revenue Calculator in Seller Central before making a decision.

Can I use these calculators for marketplaces outside the United States?

Yes, the arithmetic is the same in any marketplace as long as you enter that marketplace's fees and use one currency consistently throughout. Remember that VAT or GST changes the maths in several regions, so treat the result as pre-tax and confirm the tax treatment for your registration.

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