Ecommerce Profit Calculator — Calculate Amazon FBA Fees, Margins & ROAS Free

Why Most Online Sellers Underestimate Their Costs

Many first-time ecommerce sellers focus on their buying price and selling price and ignore the full cost stack. The result? They run campaigns, make sales, and still lose money. The hidden costs that erode ecommerce profit include:

Platform fees (Amazon referral fee: 6–15%, Flipkart commission: 5–20%)
Fulfilment fees (Amazon FBA picking, packing, and storage charges)
Shipping and return handling costs
Customer acquisition cost (CAC) from paid ads
GST/TDS on marketplace payouts
Cost of returns (India ecommerce return rates can be 15–30% for fashion)
Payment gateway fees (Razorpay, PayU: ~2%)

Our collection of 60+ free ecommerce calculators helps you account for every cost before you price your product or run your first ad.

1. Product Profit Margin Calculator

The most fundamental calculation for any seller. Our profit margin calculator computes:

Gross Profit = Selling Price − Cost of Goods Sold
Gross Margin % = (Gross Profit / Selling Price) × 100
Net Profit = Selling Price − COGS − Platform Fee − Shipping − Returns − Ad Spend

Aim for at least 30% gross margin on any ecommerce product to leave room for advertising, returns, and overheads. Below 20% and it is extremely difficult to run profitable ads.

2. Amazon FBA Fee Calculator

Amazon's FBA fees include a referral fee (category-based), a fulfilment fee (size and weight-based), and monthly storage fees. These can add up to 30–40% of the selling price for small, low-value items. Our Amazon FBA calculator inputs your selling price, category, product dimensions, and weight to output exact FBA fees and net payout.

Example: A Rs. 599 fashion accessory weighing 250g might incur:

Referral fee (15%): Rs. 89.85
FBA fulfilment fee: Rs. 56 (small size, 250g)
Total Amazon fees: Rs. 145.85 (24% of selling price)
Net to seller (before COGS): Rs. 453.15

3. ROAS Calculator (Return on Ad Spend)

ROAS tells you how much revenue you earn for every rupee spent on advertising. Our ROAS calculator calculates:

ROAS = Revenue from Ads / Ad Spend

A ROAS of 4x means you earn Rs. 4 in revenue for every Rs. 1 spent on ads. But the ROAS you need to break even depends on your margins. At a 25% net margin, you need ROAS ≥ 4 just to cover ad costs. Our calculator factors in your margin to show you the minimum profitable ROAS.

4. Customer Acquisition Cost (CAC) Calculator

CAC tells you how much you spend to acquire one paying customer:

CAC = Total Marketing Spend / Number of New Customers

For a sustainable ecommerce business, your CAC must be significantly lower than your Customer Lifetime Value (LTV). The LTV:CAC ratio should ideally be at least 3:1. Our CAC calculator tracks this across channels.

5. Dropshipping Profit Calculator

Dropshipping has lower upfront investment but tighter margins. Typical costs for a dropshipper include:

Product cost from supplier
Shipping cost (international or domestic)
Platform fees (Shopify, WooCommerce hosting)
Payment gateway fees (~2%)
Ad spend (Facebook, Instagram, Google Shopping)
Return handling

Our dropshipping profit calculator helps you quickly identify whether a product can be profitable before you spend money on ads.

6. Break-Even Sales Volume Calculator

Before scaling ad spend, you need to know how many units you need to sell to cover your fixed costs. Our break-even calculator uses:

Break-even Units = Fixed Costs / (Selling Price − Variable Cost per Unit)

For a product with Rs. 300 contribution margin and Rs. 30,000 monthly fixed costs, you need 100 units/month to break even.

7. Import Duty and Customs Calculator

If you are importing products from China or other countries, customs duty and IGST add significantly to your landed cost. Our customs duty calculator computes BCD (Basic Customs Duty), Social Welfare Surcharge, and IGST on the CIF value to show your full landed cost.

Building a Profitable Product Stack

Use these calculators as a checklist before launching any product:

Calculate your product cost including import duty if applicable
Research competitor prices to set a realistic selling price
Plug into the FBA or platform fee calculator to get net payout
Calculate your minimum ROAS to break even on ads
Set a CAC target based on your LTV:CAC goal
Run the profit margin calculator to confirm viability

Any product with less than 25% net margin after all fees and a 10% assumed return rate is very difficult to scale profitably through paid advertising in India's competitive D2C market.