What Platform Should You Sell On? (Profit Margin Calculator)

E-Commerce9 min read

Every Platform Takes a Different Cut

Every e-commerce platform advertises how easy it is to sell with them. None of them make it easy to understand how much they actually take.

Amazon charges a 15% referral fee. Etsy takes 6.5% plus a 3% payment processing fee plus a $0.25 listing fee. Shopify charges 2.9% + $0.30 per transaction. eBay takes 13.25%. TikTok Shop is at 5%. And then there's the monthly fees, the FBA fees, the promoted listing costs.

I built the Profit Margin Calculator because I got tired of doing this math on a napkin every time someone asked me "should I sell on Amazon or Shopify?" The answer is always "it depends on your numbers." Now there's a fast way to see those numbers side by side.

The Fee Breakdown Nobody Explains Clearly

I've sold on Shopify, Etsy, Amazon, and eBay. These aren't hypothetical fees. These are the fees I've paid.

  • Shopify: No referral fee. 2.9% + $0.30 payment processing. $39/month subscription. You drive your own traffic.
  • Amazon (FBA): 15% referral fee plus storage and fulfillment fees ($3-10+ per item). Massive built-in audience of 300M+ active accounts.
  • Etsy: $0.20 listing fee + 6.5% transaction fee + 3% + $0.25 payment processing. On a $50 item, that's about $5 in combined fees. I've done over $53K on Etsy with 5-star shops.
  • eBay: 13.25% final value fee. Payment processing included. First 250 listings/month free.
  • TikTok Shop: 5% referral fee. Lowest rate of any major marketplace right now.
  • Walmart: 12% referral fee (8-15% by category). No monthly fees. More selective application process.

How the Calculator Works

You enter your product details once and see the results across every platform simultaneously. Enter your selling price, product cost, shipping cost, and optional ad spend. You get revenue, fees, costs, profit, margin percentage, and ROI for every platform at once.

Enter your product details once and compare real profit margins across every platform. Free, instant.

Try the Profit Margin Calculator

What the Numbers Usually Reveal

After running the calculator for thousands of scenarios across my own businesses and client work, here are the patterns:

  • Shopify wins on margin if you have traffic. You're only losing 2.9% + $0.30 to payment processing.
  • Amazon wins on volume. Lower margin per unit, but Amazon's traffic does the selling for you.
  • Etsy is expensive but targeted. 9.5%+ in combined fees, but the audience is specifically looking for handmade and creative products.
  • TikTok Shop is the cheapest for now. At 5%, you keep more per sale than any other marketplace.
  • Most sellers should be on multiple platforms. List on 2 to 3 and compare real performance over 90 days.

Example Scenarios

Here's how the math plays out in real scenarios:

Handmade candle, $35 (product cost $8, shipping $5): Shopify profit $20.69 (59.1%), Etsy $18.32 (52.3%), Amazon $16.49 (47.1%). Shopify wins per unit, but only if you're driving traffic.

Electronics accessory, $49.99 (product cost $12, shipping $4): Shopify $32.54 (65.1%), Amazon $26.49 (53.0%), Walmart $27.99 (56.0%). Amazon's 15% fee takes a bite, but volume potential is highest.

Digital download, $19.99 (no cost of goods): Shopify $19.11 (95.6%), Etsy $17.99 (90.0%), TikTok Shop $18.99 (95.0%). Digital products show the fee difference most clearly.

Frequently Asked Questions

The calculator focuses on per-transaction fees so you can compare apples to apples across platforms. Shopify's $39/month Basic plan isn't included in the per-unit math. To factor it in, divide your monthly subscription by your expected units sold and add that to your cost. The Profit Margin Calculator breaks down the exact fee structure for each platform so you see where your money goes.

The calculator includes Amazon's 15% referral fee, which is the main per-sale cost. FBA fulfillment fees vary by product size and weight, so you should add those to your shipping cost input. Amazon publishes their FBA fee schedule by product tier. For most standard-size items, expect $3 to $5 on top of the referral fee.

No. The calculator runs entirely in your browser. Product prices, costs, and margin calculations are never sent to a server or saved anywhere. Same approach across all tools in the free suite.

No. Margin is one variable. Volume, audience fit, competition, and operational complexity all matter. A 50% margin on 10 sales a month is worse than a 40% margin on 100 sales. That's why I recommend most sellers list on 2 to 3 platforms and compare real performance over 90 days. The Profit Margin Calculator lets you run side-by-side comparisons so you can make that call with real numbers.

See Your Real Margins

Enter your product details once and compare profit margins across Shopify, Amazon, Etsy, eBay, TikTok Shop, and Walmart. Free, instant, runs in your browser.

Open the Profit Calculator