SellerKit Marketplace Seller Tools

Know Your Real Profit Before You List

Marketplace fees quietly eat 15–30% of every sale. SellerKit shows you the exact fee breakdown for Amazon, eBay, Etsy and Shopify — before you price a single item. Every calculator runs free, right in your browser.

10 free calculators Runs 100% in your browser No sign-up, no uploads Itemized fee breakdowns

Showing all 10 tools

Marketplace Fees

Amazon FBA Fee & Profit Calculator

See exactly what Amazon keeps from every FBA sale — referral fee, fulfillment fee and inbound shipping — and what profit is actually left. Built for Amazon sellers checking a product before they order stock.

Fee rates as of 2026 — marketplaces change fees, always confirm current rates before pricing.

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$ Your cost to ship one unit into an Amazon fulfillment center.
Marketplace Fees

eBay Fee Calculator

Work out eBay's final value fee — the percentage plus the fixed per-order fee — on any listing, including the discount if you run an eBay Store. Made for eBay sellers who want the real payout number, not a surprise.

Fee rates as of 2026 — marketplaces change fees, always confirm current rates before pricing.

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eBay charges a fixed $0.30 fee on orders up to $10, and $0.40 above $10 — applied automatically.
Marketplace Fees

Etsy Fee Calculator

Add up every Etsy charge on an order — the $0.20 listing fee, 6.5% transaction fee, payment processing and the regulatory fee — so you can price handmade and vintage items with your margin intact. For Etsy shop owners of any size.

Fee rates as of 2026 — marketplaces change fees, always confirm current rates before pricing.

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% Charged on the order total. US sellers: 1.15%. It varies by country — check your Etsy dashboard.
Marketplace Fees

Shopify Cost Calculator

Compare what a Shopify plan really costs per month once card processing and third-party gateway fees are added — and see your true cost per order. For store owners deciding whether a bigger plan actually saves money.

Fee rates as of 2026 — marketplaces change fees, always confirm current rates before pricing.

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% Shopify adds a transaction fee on those orders: 2% Basic, 1% Grow, 0.6% Advanced.
Pricing

Required Selling Price Calculator

Work backwards from the profit you want: enter your costs, the marketplace fee percentage and your target margin, and get the exact price to list at. For any seller who prices by margin instead of guessing.

Fee rates as of 2026 — marketplaces change fees, always confirm current rates before pricing.

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% All percentage fees combined, as a share of the selling price.
% Profit as a share of the selling price — not markup on cost.
Pricing

Markup Calculator

Turn a cost and a markup percentage into a selling price, your gross profit per unit, and the margin that markup really gives you. For sellers and small retailers who price from cost upwards.

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Pricing

Bundle Pricing Calculator

Price a bundle of up to five products with a discount that still protects your profit: see the bundle price, what buyers save versus buying separately, and your total profit per bundle. For sellers building kits, sets and “frequently bought together” offers.

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Operations

Shipping & DIM Weight Calculator

Carriers charge on whichever is heavier: your package's actual weight or its dimensional (DIM) weight. Enter the box size and weight to see both numbers and which one you'll actually be billed on — before a surprise carrier invoice arrives.

Operations

Inventory Turnover Calculator

Find out how many times a year your stock sells through, and how many days the average item sits on the shelf. For sellers who want to free up cash trapped in slow-moving inventory — or spot stock-outs before they happen.

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$ Typical value of stock on hand, at cost, across the year.
Operations

Returns Cost Calculator

Returns are a silent profit killer. This tool totals what returns really cost you each month — return shipping, handling and unsellable stock — and shows your profit after returns are taken out. For any seller whose return rate is creeping up.

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% Your profit margin before returns — used for the “profit after returns” line.
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% Example: 20% means one fifth of a returned item's value is lost to damage, opened packaging or markdowns.
No tool matches that search Try “fees”, “profit”, “shipping” or “returns” — or clear the search to see all 10 tools.

About SellerKit

SellerKit is a free set of calculators built for people who sell on Amazon, eBay, Etsy and Shopify in the USA, UK, Canada and Australia. Marketplace fees are complicated on purpose — referral fees, fulfillment fees, per-order fees and processing charges stack up fast, and a price that “looks profitable” often isn't.

Every tool here shows its working: you get the itemized breakdown, not just a total, so you can check the math yourself. All calculations happen in your browser — your prices, costs and margins are never uploaded anywhere.

Contact

Spotted a fee rate that has changed, or want a calculator we don't have yet? Marketplace fees move often and we update SellerKit's presets as they do — a quick note from a working seller helps more than anything.

Email us any time and we'll get back to you.

[email protected]