Hold the order sample constant
The comparison uses the same item price, shipping, COGS, fulfillment, ad spend and refund reserve on every platform. That isolates platform fees as the variable.
It does not claim the same order would sell on every platform. Traffic, conversion, returns and customer mix can differ far more than fees.
What each platform charges
Shopify has a monthly subscription plus payment processing. Etsy has listing amortization, transaction, payment and expected offsite ads. TikTok Shop has referral, affiliate, payment and a fixed fee. Amazon is modeled as a referral fee, with fulfillment kept in the common cost.
The assumptions table shows the exact rates. They are planning presets, not live quotes.
Worked example
Item $50, shipping $5, COGS $15, fulfillment $7, ads $5, refund 5% × $15. Common costs are $27.75 including the $0.75 refund reserve.
Net revenue is $24.97 on Shopify, $20.93 on Etsy, $14.91 on TikTok Shop and $19.00 on Amazon. The spread between the highest and lowest is $10.06 per order.
Read the gap, not the winner
A $10 spread is material, but it is not a platform verdict. If Etsy brings converting traffic that Shopify does not, the net per order can be lower while total profit is higher.
Use the comparison to quantify the fee handicap, then combine it with traffic, conversion, AOV and repeat purchase data before choosing a channel.
Refunds and monthly fees
The refund reserve is common across platforms, so changing the refund rate shifts every net by the same amount in this model. Real platforms may reverse different fees, so treat the shift as a sensitivity, not a rule.
Monthly fees are amortized by order volume. At 100 orders, Shopify's $39 monthly fee is $0.39 per order; at 10 orders, it is $3.90. Low-volume stores feel fixed fees much more.
Where the comparison stops
It excludes taxes, currency conversion, marketplace-specific ad auctions, storage, inbound freight, category-specific rates, promotions and brand effects. Amazon fulfillment is kept in the common fulfillment input rather than modeled as FBA.
Use the single-platform calculators to edit detailed rates. Use this page to see the relative gap under one transparent sample.