Enter Your Costs
Input every per-unit cost: COGS, labor, shipping, gateway fees, marketplace cuts, and return rates.
100% Client-Side · Your Numbers Never Leave
A ROAS margin calculator reveals your true e-commerce net profit margin after all costs — COGS, shipping, gateway fees, returns, and labor — then calculates the break-even ROAS you must exceed for paid advertising on Facebook, TikTok, or Google to be profitable.
Your Unit Economics
Margin Breakdown
Enter your numbers to see the waterfall.
Results update in real-time as you type.
Net Profit
True Margin
Break-Even ROAS
Max CPA
What If? ROAS Scenarios
See your profitability at different return-on-ad-spend levels.
| ROAS | Ad Spend / Sale | Profit After Ads | Margin After Ads |
|---|---|---|---|
| Enter your costs above to generate ROAS scenarios. | |||
How It Works
See the Waterfall
Watch your selling price shrink step-by-step to reveal your true net margin in a visual waterfall chart.
Know Your ROAS Floor
Get the exact minimum ROAS and maximum CPA you need before ads become unprofitable.
Run Scenarios
See your profitability at different ROAS levels from 1x to 20x in an instant scenario table.
E-Commerce Tech Stack Essentials
Tracking your true margin manually is exhausting and prone to errors. To automate this process across your store, we recommend integrating a dedicated e-commerce accounting software suite with your Shopify or WooCommerce backend. For dropshippers or FBA sellers with tight margins, utilizing an automated repricing tool can help you stay competitive while protecting your break-even ROAS floor.
What is Break-Even ROAS?
Return on Ad Spend (ROAS) is a common metric in digital marketing, but a positive ROAS doesn't guarantee a profitable business. Break-Even ROAS is the absolute minimum return you need from your ad spend (on Facebook, Google, or TikTok) to cover the cost of the product, shipping, payment gateway fees, marketplace commissions, and the ads themselves. If your actual ROAS falls below this number, you are losing money on every sale. MarginMax takes all your variable costs into account to reveal your true Net Profit Margin per unit. By knowing your exact profit margin before ads, you can mathematically determine your Break-Even ROAS and maximum acceptable Cost Per Acquisition (CPA), allowing you to scale your advertising campaigns with confidence.
Frequently Asked Questions
What is break-even ROAS and how do you calculate it?
Break-even ROAS (Return on Ad Spend) is the minimum ROAS needed to cover your costs — at this point, you make $0 profit. Calculate it as: Break-Even ROAS = 1 / Net Profit Margin. If your true net margin is 20%, your break-even ROAS is 1/0.20 = 5.0x. Below 5.0x, you're losing money on every ad-driven sale.
What is a good ROAS for Facebook or TikTok ads?
A 'good' ROAS depends entirely on your profit margins. A 4x ROAS is unprofitable if your margins are under 25%. Most e-commerce brands target 3x-5x ROAS, but the only number that matters is whether your ROAS exceeds your break-even ROAS. Calculate your true net margins first — most sellers overestimate them by ignoring pick/pack labor, returns, and gateway fees.
Why is my ROAS good but I'm still not profitable?
The most common cause is underestimating true COGS. Sellers often include only product cost but forget: shipping to customer, payment gateway fees (2.9% + $0.30), returns and refund processing, pick/pack labor, packaging materials, and platform fees. When all costs are included, a seemingly healthy 4x ROAS can actually be break-even or worse.