Amazon FBA vs Shopify Fee Calculator
Compare Amazon FBA referral and fulfillment fees against standalone Shopify payment processing, 3PL shipping, and ad spend CAC.
Product Economics & Channel Specs
If Facebook/Google ads cost more than this amount per customer, Amazon FBA delivers higher take-home profit.
๐ก The Omnichannel Secret
Successful e-commerce brands rarely pick just one. They use Amazon FBA for fast customer discovery and high conversion, and build their Shopify store for long-term customer email retention and repeat subscriptions.
E-Commerce Channel Margin Formula
Amazon Profit = Revenue โ COGS โ (Pro Plan + 15% Referral + FBA Fulfillment + Storage); Shopify Profit = Revenue โ COGS โ (Shopify Plan + 2.9% Payment + 3PL Shipping + Ad Spend CAC)- Retail Price & COGS: Consumer purchase price minus manufactured landed cost per unit.
- Amazon Referral Fee: Universal 15% marketplace commission on gross customer transaction value.
- FBA Pick & Pack: Amazon warehouse storage, picking, packaging, and Prime 2-day domestic transport.
- Shopify Payment Gateway: Standard merchant credit card interchange fee (2.9% + $0.30 per transaction).
- Ad Spend (CAC): Paid traffic acquisition cost per unit required to drive independent storefront sales.
Step-by-Step Worked Example
Calculation Steps:
- Amazon Total Operating Expenses = $4,500 (COGS) + $2,625 (Referral) + $2,375 (FBA) + $140 = $9,640.00
- Amazon Monthly Net Profit = $17,500 โ $9,640 = $7,860.00 (44.9% Net Margin ยท $15.72/unit)
- Shopify Total Operating Expenses = $4,500 (COGS) + $658 (Processing) + $2,750 (Shipping) + $3,500 (Ads) + $39 = $11,447.00
- Shopify Monthly Net Profit = $17,500 โ $11,447 = $6,053.00 (34.6% Net Margin ยท $12.11/unit)
- Comparison Verdict: Amazon FBA yields $1,807.00 more profit per month because organic buyer traffic eliminates ad dependency.
How to Use This Calculator
- 1Enter your product retail price with your chosen currency and unit manufacturing cost (COGS).
- 2Input projected monthly sales volume in units.
- 3Review Amazon FBA fees (15% referral fee and standard parcel pick/pack).
- 4Enter your Shopify merchant processing, warehouse 3PL postage, and customer acquisition cost (CAC).
- 5Check the Break-Even CAC metric to see the maximum ad spend Shopify can tolerate before Amazon becomes more lucrative.
Assumptions & Limitations
- Assumes standard domestic customer deliveries without oversized or hazmat surcharges.
- Amazon referral fee reflects the standard 15% rate applicable to the majority of consumer product categories.
- Shopify model assumes customer acquisition relies on paid digital advertising (Meta, Google, TikTok Ads).
Frequently Asked Questions
Why does Amazon FBA often deliver higher margins than Shopify for new products?
Amazon has over 300 million active consumer accounts with Prime high-intent buying behavior. On Shopify, the brand must pay $5 to $15+ per customer in advertising to generate traffic, which often exceeds Amazonโs 15% referral commission.
When does a Shopify store beat Amazon FBA?
Shopify wins when you have strong organic branding, viral social media traffic, high email repeat purchase rates (LTV), or sell customizable/subscription products where advertising cost per order is near zero.
What is the "Break-Even Ad Spend" metric?
Break-even ad spend is the maximum Customer Acquisition Cost (CAC) you can afford on Shopify while matching Amazonโs net take-home profit. If your paid ads exceed this number, Amazon generates more cash in your bank.
Related Cost Calculators
Cost Per Use Calculator
Calculate the true cost per wear or use of any purchase based on price, expected lifespan, resale value, and maintenance.
Freight Dimensional Weight Calculator
Calculate DIM weight divisors for FedEx, UPS, and DHL air/ground shipments.
SaaS Pricing Tier & Margin Calculator
Model MRR, churn rate, customer acquisition cost (CAC), and customer lifetime value (LTV).