What Is Amazon FBA and How Do Fees Work?
Fulfillment by Amazon (FBA) is a service where Amazon stores, picks, packs, ships, and handles customer service for your products. In exchange, sellers pay a combination of referral fees (a percentage of the sale price), fulfillment fees (per-unit handling and shipping), and monthly storage fees based on product volume. Understanding these fees is critical because they directly determine your profit margin on every unit sold.
The 2026 US FBA fee structure includes a 3.5% fuel surcharge on referral fees introduced in April 2026, and a low-price FBA discount of $0.86 for items priced under $10. This calculator incorporates all current 2026 rates so you get an accurate picture of your true per-unit cost before committing to inventory.
FBA vs FBM — Fee Comparison
FBA (Fulfilled by Amazon)
- Prime eligibility & Buy Box advantage
- Amazon handles shipping & returns
- Referral fee: 8–17% + 3.5% fuel surcharge
- Fulfillment fee: $3.22–$22.70+ per unit
- Storage: $0.78–$1.02/cu ft/month
- Best for: lightweight, high-volume products
FBM (Fulfilled by Merchant)
- You handle storage, shipping, returns
- Referral fee only (8–17% + fuel surcharge)
- No fulfillment or storage fees
- You control packaging & branding
- Best for: heavy, slow-moving, niche products
- Lower fees but more operational work
FBA Profit Formula — How to Calculate Amazon Profit
Net Profit = Sale Price − Referral Fee − Fuel Surcharge − FBA Fee − Storage − Product Cost − Shipping
How to Use This Amazon FBA Calculator
- Enter your sale price — the price your product sells for on Amazon.
- Enter product cost and shipping — your landed cost per unit (manufacturing + shipping to FBA warehouse).
- Enter dimensions and weight — length, width, height in inches and weight in pounds. The calculator auto-detects your FBA size tier.
- Select your category — this sets the correct referral fee rate (8-17%).
- Enter monthly units and storage months — for revenue and monthly profit projections.
- Review your results — see the complete fee breakdown, net profit, margin, ROI, break-even price, and a visual fee comparison chart.
2026 Amazon FBA Size Tiers Explained
| Size Tier | Max Weight | Max Dim Sum | Max Longest Side | Base Fee |
|---|---|---|---|---|
| Small Standard | 12 lb | 25 in | 18 in | $3.22 |
| Large Standard | 20 lb | 52 in | 22 in | $4.75 + $0.38/lb over 1 |
| Large Bulky | 70 lb | 165 in | 108 in | $9.73 + $0.63/lb over 1 |
| Extra-Large | 150 lb | 165 in | 108 in | $18.49 + $0.80/lb over 1 |
| Oversize | 150+ lb | 165+ in | 108+ in | $22.70 + $0.90/lb over 1 |
Dimensional weight is calculated as (L × W × H) ÷ 139. Billable weight = max(actual weight, dimensional weight). Size tier is auto-detected in this calculator from the dimensions and weight you enter.
Category Referral Fee Rates — 2026 US Marketplace
| Category | Referral Fee Rate | Notes |
|---|---|---|
| Electronics | 8% | Lowest referral rate; high competition |
| Grocery & Gourmet | 8–15% | Varies by sub-category and price point |
| Books, Music, Video | 15% | Standard rate for media categories |
| Most Categories | 15% | Home, Sports, Beauty, Toys, etc. |
| Clothing & Accessories | 17% | Highest standard referral rate |
A 3.5% fuel surcharge is applied on top of the referral fee for all categories since April 2026. This calculator adds the fuel surcharge automatically.