How to Calculate Amazon FBA Profit - Complete Step-by-Step Guide

Calculating Amazon FBA profit accurately is essential for making informed business decisions. This comprehensive guide walks you through every step, formula, and consideration needed to determine your true profit margins.

Why Accurate Profit Calculation Matters

Many Amazon sellers lose money because they don't account for all fees and costs. Accurate profit calculation helps you:

  • Make informed product sourcing decisions
  • Avoid listing unprofitable products
  • Set competitive yet profitable prices
  • Plan for growth and scaling
  • Identify areas to reduce costs

Use our free FBA profit calculator to automate these calculations, or follow the manual steps below.

Step 1: Calculate Gross Revenue

Formula

Gross Revenue = Selling Price × Quantity Sold

This is your total sales before any deductions.

Example

If you sell 100 units at $25 each:

Gross Revenue = $25 × 100 = $2,500

Step 2: Calculate Product Costs

Formula

Product Cost = Cost Per Unit × Quantity

Include manufacturing, sourcing, and any product-related expenses.

Example

If each unit costs $8 and you sell 100 units:

Product Cost = $8 × 100 = $800

Tip: Include all costs: manufacturing, quality control, customs, duties, and any product modifications.

Step 3: Calculate Amazon Referral Fees

Amazon charges a referral fee based on your product category. This is a percentage of your selling price.

Formula

Referral Fee = Gross Revenue × Referral Rate

Referral rates vary by category (typically 8-20%).

CategoryReferral Rate
Electronics8%
Home & Kitchen15%
Clothing & Fashion17%
Beauty & Personal Care15%

Example

For Home & Kitchen (15% referral rate) with $2,500 gross revenue:

Referral Fee = $2,500 × 0.15 = $375

Step 4: Calculate FBA Fulfillment Fees

FBA fulfillment fees depend on your product's size and weight. Amazon uses size tiers to determine these fees.

Formula

FBA Fee = FBA Fee Per Unit × Quantity

Fees range from $3.22 (small standard) to $75+ (large oversize).

Example

For a small standard item ($3.22 per unit) with 100 units:

FBA Fee = $3.22 × 100 = $322

Tip: Optimize your product dimensions to fit into smaller size tiers and reduce fees.

Step 5: Calculate Storage Fees

Amazon charges monthly storage fees based on the volume your inventory occupies. Fees are higher during peak season (October-December).

Formula

Storage Fee = Cubic Feet × Rate × Months

Rates: $0.75/cubic foot (Jan-Sep) or $2.40/cubic foot (Oct-Dec).

Example

For 2 cubic feet stored for 3 months during standard season:

Storage Fee = 2 × $0.75 × 3 = $4.50

Warning: Storage fees triple during Q4. Plan inventory carefully to avoid excessive costs.

Step 6: Calculate Other Costs

Don't forget these additional costs that impact your profit:

Shipping to AmazonVariable (typically $50-$500)
Packaging & Labeling$0.10-$0.50 per unit
Return Processing Fees$2.12+ per return
Advertising (PPC)20-30% of revenue (typical)
PhotographyOne-time cost

Step 7: Calculate Total Costs

Formula

Total Costs = Product Cost + Referral Fee + FBA Fee + Storage Fee +
Shipping + Packaging + Returns + Advertising + Other Costs

Example Calculation

Product Cost:$800
Referral Fee (15%):$375
FBA Fee:$322
Storage Fee:$5
Shipping:$150
Packaging:$25
Advertising (25%):$625
Total Costs:$2,302

Step 8: Calculate Net Profit

Formula

Net Profit = Gross Revenue - Total Costs

Example

With $2,500 gross revenue and $2,302 total costs:

Net Profit = $2,500 - $2,302 = $198

Step 9: Calculate Profit Margin and ROI

Profit Margin

(Net Profit / Gross Revenue) × 100

Example: ($198 / $2,500) × 100 = 7.92%

ROI (Return on Investment)

(Net Profit / Total Costs) × 100

Example: ($198 / $2,302) × 100 = 8.6%

Common Calculation Mistakes

  • Forgetting storage fees: Especially during peak season when fees triple
  • Not accounting for returns: Return processing fees add up quickly
  • Ignoring long-term storage: Items stored 365+ days incur additional fees
  • Underestimating advertising: PPC costs can be 20-40% of revenue
  • Using wrong category: Higher referral fees significantly impact profit
  • Not including all shipping costs: Both to Amazon and customer returns

Use Our Free Calculator

Don't want to calculate manually? Use our free Amazon FBA Profit Calculator that automatically accounts for all fees, costs, and marketplace differences. Get accurate profit calculations in seconds.

Calculate Profit Now →