How to Calculate Real Profit for Your Ecommerce Business (Not Just Revenue)

Your Revenue Dashboard Is Lying to You

Every ecommerce platform shows you a big, satisfying revenue number. Shopify puts it front and center. Amazon Seller Central highlights your total sales. Stripe shows gross volume.

But none of these numbers tell you what you actually made. Revenue is vanity. Profit is reality.

If you're running an ecommerce business and you don't know your exact net profit — down to the dollar — you're making decisions in the dark. Pricing decisions. Ad spend decisions. Inventory decisions. All based on a number that doesn't account for the dozens of costs eating into your margins.

Let's fix that.

The Ecommerce Profit Formula

At its core, the profit formula is simple:

Net Profit = Revenue − COGS − Operating Expenses

But the devil is in the details. Here's what each piece actually includes for an ecommerce business:

Revenue (What You Collected)

Start with your gross sales — the total dollar amount of all orders. Then subtract:

• Refunds — Full or partial refunds issued to customers
• Chargebacks — Disputed transactions where the payment processor reversed the charge
• Discounts — Coupon codes, sale prices, loyalty rewards

What remains is your net revenue. This is the real starting point, not the gross sales number your dashboard shows.

Cost of Goods Sold (COGS)

COGS is what it costs you to deliver the product to the customer. This includes:

• Product cost — What you paid your supplier or manufacturer per unit
• Inbound shipping/freight — Getting products from your supplier to your warehouse or Amazon FBA
• Platform fees — Shopify's 2.9% + $0.30 per transaction, Amazon's 15% referral fee, Amazon FBA fees
• Payment processing — Stripe fees (2.9% + $0.30), PayPal fees, or other processor charges
• Outbound shipping — What you pay to ship orders to customers (if not already included in product cost)
• Packaging materials — Boxes, mailers, tape, inserts, branded packaging

Many sellers only count the product cost as COGS and forget everything else. That's a mistake that makes your gross margin look 15-25% higher than it actually is.

Operating Expenses

These are the costs of running your business that aren't directly tied to individual products:

• Advertising — Facebook Ads, Google Ads, TikTok Ads, Amazon PPC, influencer payments
• Software subscriptions — Shopify plan ($39-399/month), email marketing, inventory management, design tools
• Warehouse/storage — Rent, Amazon FBA storage fees, 3PL monthly costs
• Returns processing — Restocking, return shipping labels, lost inventory from returns
• Insurance — Business liability, product liability, shipping insurance
• Professional services — Bookkeeper, accountant, virtual assistant, freelancers
• Miscellaneous — Office supplies, internet, phone, travel to trade shows

A Real-World Example

Let's say you sell a product on Shopify for $50 and you process 1,000 orders in a month.

Gross Revenue: $50,000

Subtract returns (8%): -$4,000

Net Revenue: $46,000

COGS breakdown:

• Product cost ($12/unit × 1,000): $12,000
• Shopify fees (2.9% + $0.30 × 1,000): $1,636
• Stripe processing (already in Shopify fees for Shopify Payments): $0
• Outbound shipping ($5.50/order × 1,000): $5,500
• Packaging ($1.25/order × 1,000): $1,250

Total COGS: $20,386

Gross Profit: $25,614 (55.7% gross margin)

Operating expenses:

• Facebook Ads: $8,000
• Shopify plan: $79
• Email marketing tool: $50
• Return shipping labels: $600
• Warehouse rent: $1,200

Total Operating Expenses: $9,929

Net Profit: $15,685

Net Profit Margin: 34.1%

Your Shopify dashboard showed $50,000 in revenue. Your actual profit was $15,685. That's a 69% difference between what your dashboard shows and what you actually earned.

The Costs Most Sellers Forget

After working with hundreds of ecommerce sellers, these are the costs that get missed most often:

Return costs are bigger than you think. When a customer returns a $50 item, you don't just lose the $50 in revenue. You lose the outbound shipping cost, the return shipping cost, the original payment processing fee (which isn't refunded), and often the product itself if it can't be resold. A single return can cost you $15-25 in pure loss beyond the refund.

Amazon FBA fees are layered. Amazon charges a referral fee (usually 15%), an FBA fulfillment fee ($3-8+ depending on size/weight), monthly storage fees, and long-term storage fees for items sitting over 365 days. Many Amazon sellers only track the referral fee.

Payment processing fees on refunds aren't returned. When you refund a customer, Stripe and most processors keep their processing fee. On a $50 refund, you're out $1.45 that you'll never get back.

Ad spend attribution is tricky. You might spend $8,000 on Facebook Ads that generate $30,000 in attributed revenue. But some of those customers would have bought anyway. And the Facebook attribution window may be counting conversions that were really driven by other channels.

How to Calculate Your Profit Margin

There are two margins you should track:

Gross Profit Margin = (Net Revenue − COGS) / Net Revenue × 100

This tells you whether your products are fundamentally profitable. A healthy ecommerce gross margin is typically 50-70% depending on your category. If yours is below 40%, you may have pricing or sourcing issues.

Net Profit Margin = Net Profit / Net Revenue × 100

This is your bottom line. For ecommerce businesses, a healthy net margin is 10-20%. Top performers hit 25%+. If you're below 10%, you're vulnerable — one bad month of returns or a spike in ad costs could push you into the red.

Stop Doing This in Spreadsheets

You can absolutely calculate all of this in a spreadsheet. But if you're processing hundreds or thousands of transactions per month, manual entry is a recipe for errors and wasted time.

This is exactly what FreePNL automates. Upload your bank statement or Shopify/Amazon export as a CSV, and AI categorizes every transaction into the right P&L category automatically. In under 60 seconds, you get a professional profit and loss statement showing your gross profit, operating income, net income, and all your margins.

The Free plan lets you generate one P&L per week. No credit card, no complicated setup, no accounting degree required.

Key Takeaways

Your ecommerce profit is almost certainly lower than you think. The gap between revenue and net profit is where businesses succeed or fail, and the only way to know your real number is to track every cost.

Start by calculating your true COGS — including platform fees, payment processing, and shipping. Then layer in your operating expenses. The resulting net profit number is what you should be optimizing for, not revenue.

If you want to skip the spreadsheet and get your numbers in 60 seconds, try FreePNL for free.