Free tools · No signup · Zero data collected

Know your real profit before you sell.

Referral fees, fulfillment, payment processing, Offsite Ads — platforms take their cut before you ever see a dollar. Run the numbers first, then decide what to list, where, and at what price.

  • 9 seller calculators
  • $0 forever, no account
  • 100% in-browser math

The toolbox

Pick the math you need

Every calculator is live — change any number and the receipt updates instantly. Nothing to install, nothing to sign up for.

Amazon FBA

Amazon FBA Profit Calculator

Price in referral fees, FBA fulfillment, storage, and inbound shipping to see true profit, margin, ROI, and your break-even price per unit.

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Shopify

Shopify Profit Margin Calculator

Includes Shopify plan transaction fees and payment processing, so your margin reflects what actually lands in the bank on every order.

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Etsy

Etsy Fee & Profit Calculator

Adds up the $0.20 listing fee, 6.5% transaction fee, payment processing, and Offsite Ads to reveal real profit on every Etsy sale.

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Paid Ads

ROAS & Break-Even Calculator

Find your break-even ROAS before you scale spend. Compare it with actual campaign ROAS to know if your ads print money or burn it.

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Pricing

Discount Pricing Calculator

Price percentage-off, BOGO, and spend-threshold deals against your real margin. See profit per unit after the discount and the maximum you can afford to give.

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Pricing

Break-Even Units Calculator

Find the exact number of units you must sell to cover fixed costs. See how price, margin, and ad spend shift your break-even point — before you commit inventory.

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TikTok

TikTok Shop Fee Calculator

Calculate TikTok Shop referral fees, affiliate commissions, and ad spend to see real profit per order. Includes category presets and refund admin fees.

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eBay

eBay Fee & Profit Calculator

Factor in final value fees by category, per-order charges, insertion fees, promoted listings, and Store subscriber savings to see true profit on every eBay sale.

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Compare

Platform Fee Comparison

Enter your price and cost once — instantly compare profit, fees, and margin across Amazon, eBay, Etsy, Shopify, and TikTok Shop. Find the most profitable platform in seconds.

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Why sellers calculate first

A $30 sale is rarely $30

Most listings die from optimistic math: sellers price against the sticker, not against the fee stack. By the time referral fees, fulfillment, processing, storage, and inbound freight take their share, a "healthy" price can leave you working for free.

The fix is boring and effective: run unit economics before you buy inventory or launch ads. Every tool here exists to answer one question — after everyone takes their cut, what's left for you?

  1. 01

    Price with the fee stack, not against it

    See every deduction line by line, exactly like the receipt.

  2. 02

    Find your break-even before you commit

    Know the minimum viable price for any product, ad, or channel.

  3. 03

    Compare platforms on true margin

    The same product can be profitable on Etsy and a loss on Amazon.

Questions

Frequently asked

Are these calculators really free?

Yes — every calculator on emallsoon is free, with no signup, no email wall, and no usage limits. The tools run entirely in your browser, so your numbers never touch a server.

How accurate are the fee rates?

We prefill each calculator with current published fee structures (Amazon referral and FBA fees, Shopify plan transaction fees, Etsy listing/transaction/payment fees, eBay final value fees by category). Rates change often and vary by category and country, so every field is editable — treat the defaults as a starting point and verify exact rates in Seller Central or your platform dashboard.

Do you store the numbers I enter?

No. All math happens locally in your browser with JavaScript. Nothing is sent to, or stored on, any server.

Which platforms do the tools cover?

Amazon FBA, Shopify, Etsy, TikTok Shop, eBay, a cross-platform fee comparison tool, paid-ad ROAS, discount pricing, and break-even units math that applies to any platform. More calculators are added regularly.