Break-Even ACoS Calculator

About the Break-Even ACoS Calculator

Your break-even ACoS is the maximum ACoS at which your Amazon PPC campaigns are still profitable. It equals your pre-advertising profit margin. If your margin before ad costs is 35%, any ACoS below 35% generates profit on ad-driven sales, and any ACoS above 35% means you're losing money.

Calculating break-even ACoS requires knowing all costs: product cost, shipping to FBA, FBA fulfillment fees, Amazon referral fee, and any other per-unit costs. Many sellers overestimate their margin and break-even ACoS by missing one or more cost components.

This calculator accounts for the major Amazon selling costs so you can use break-even ACoS as a real maximum when setting up and optimizing PPC campaigns.

When This Page Helps

Knowing your break-even ACoS is essential for profitable PPC bids. This calculator accounts for the main Amazon fee layers so you can set targets without overstating margin.

How to Use the Inputs

1. Enter the product selling price.
2. Enter COGS (landed cost per unit).
3. Enter shipping to FBA cost per unit.
4. Enter the Amazon referral fee percentage for your category.
5. Enter the FBA fulfillment fee per unit.
6. Enter any additional per-unit costs (storage, prep, etc.).
7. View your break-even ACoS and target ACoS ranges.

Example Calculation

Tips & Best Practices

• Set your campaign target ACoS at 60–70% of break-even ACoS to ensure meaningful ad profit.
• Recalculate break-even ACoS whenever COGS, FBA fees, or your selling price changes.
• Different products have different break-even ACoS — calculate separately for each ASIN.
• For product launches, you may intentionally run above break-even ACoS to build ranking.
• Higher-priced products tend to have higher break-even ACoS (more margin dollars).
• Include seasonal FBA storage fees in your "other costs" during Q4 (Oct-Dec).

Cost Components That Affect Break-Even ACoS

The most commonly overlooked costs that inflate break-even ACoS estimates: (1) Shipping to FBA ($0.50–3/unit depending on weight and origin), (2) FBA storage fees ($0.10–1+/unit/month), (3) Prep and labeling ($0.20–0.55/unit if using Amazon prep), (4) Product returns (5‒10% rate, each costing ~30% of sale price), (5) Long-term storage fees for slow sellers.

Break-Even ACoS by Product Price Point

Products priced $10‒15: Break-even ACoS typically 10‒20% (tight margins). Products priced $20‒35: Break-even typically 20–35% (sweet spot). Products priced $40–75: Break-even typically 30‒45% (more margin room). Products priced $100+: Break-even 35‒55% (best for advertising).

Using Break-Even ACoS for Bid Strategy

Max CPC = Break-Even ACoS × Sale Price × Conversion Rate. If break-even is 30%, price is $30, and conversion is 10%, max CPC = 0.30 × $30 × 0.10 = $0.90. Start bidding at 50–60% of this max and increase based on results.

Frequently Asked Questions

• What is break-even ACoS?

  Break-even ACoS is the ACoS at which you neither make nor lose money on ad-driven sales. It equals your pre-advertising profit margin. At this ACoS, your ad cost exactly equals your profit, leaving $0 net. Any ACoS below break-even is profitable; above it is unprofitable.

• How do I calculate break-even ACoS?

  Break-even ACoS = (Sale Price − All Non-Ad Costs) / Sale Price × 100. Include product cost, shipping to FBA, FBA fees, referral fees, storage fees, and any other per-unit costs. The result is the maximum percentage of ad revenue you can spend and still break even.

• What should my target ACoS be relative to break-even?

  For established products seeking profit, target 50–70% of your break-even ACoS. If break-even is 30%, target 15‒21%. For launches prioritizing ranking, you might accept 80–120% of break-even (losing money short-term to build organic position).

• Does break-even ACoS change by product size?

  Yes, significantly. FBA fees are based on product size and weight. Small/light products ($3–5 FBA fee) have higher margins and higher break-even ACoS than large/heavy products ($8–15+ FBA fee). Always use your specific product's FBA fee in the calculation.

• Should I include FBA storage fees?

  Yes, especially during Q4 (October–December) when Amazon triples storage rates. Calculate average monthly storage cost per unit based on your inventory turnover. For fast-selling products (30-day turnover), storage may add $0.10–0.30/unit. Slow sellers can add $1+/unit.

• What if my break-even ACoS is very low (under 15%)?

  A low break-even ACoS leaves little room for profitable advertising. Options: reduce COGS through better sourcing, increase the selling price, optimize FBA costs (smaller packaging, lighter materials), or focus on organic ranking-building strategies instead of direct-response PPC.