How Do You Calculate ACOS on Amazon? (Formula + Examples)

If you sell on Amazon and run PPC campaigns, ACOS (Advertising Cost of Sale) is the single most important metric you need to understand. It tells you exactly how efficiently your ad spend converts into revenue. This guide walks through the ACOS formula step by step, shows real examples, and explains how to use ACOS to make smarter campaign decisions.

1. The ACOS Formula

The ACOS formula is deceptively simple but incredibly powerful:

Breaking it down:

• Total Ad Spend — the total amount you paid for clicks across your campaign(s)
• Total Attributed Revenue — the total sales revenue generated from those ads within the attribution window
• Multiply by 100 to express the result as a percentage

The output is a percentage that tells you what portion of your revenue went to ad costs. An ACOS of 20% means you spent 20 cents in ads for every dollar of revenue earned.

2. Step-by-Step Example

Let’s walk through a real calculation. Imagine you run a Sponsored Products campaign for a portable blender on Amazon.

• Campaign period: One week
• Total ad spend: $150
• Total attributed sales: $600

Plugging into the formula:

This means for every dollar of revenue, you spent 25 cents on advertising. Whether 25% is good or bad depends entirely on your profit margin — we cover that in Section 5.

Multiple Campaign Example

If you manage several campaigns, you can calculate ACOS at the portfolio level too:

Campaign	Spend	Revenue	ACOS
Auto-Target	$80	$240	33.3%
Exact Match	$120	$600	20%
Phrase Match	$50	$160	31.3%
Portfolio Total	$250	$1,000	25%

3. Real Scenarios

Different ACOS values tell different stories about campaign health:

• ACOS below 15% — Highly efficient. You are spending very little to generate revenue. Common for brand terms or well-optimized exact-match campaigns. However, a very low ACOS may also mean you are under-spending and missing scale opportunities.
• ACOS between 15% and 30% — Healthy range for most sellers. This typically aligns with profit margins of 30-40%.
• ACOS between 30% and 50% — Worth reviewing. If your margin is less than 30%, you may be losing money. Consider lowering bids, refining keywords, or improving your listing.
• ACOS above 50% — Red flag. You are spending more than half your revenue on ads. Unless this is a launch strategy for organic rankings, reduce bids or pause the campaign.

4. Finding ACOS in Seller Central

You don’t always have to calculate ACOS manually. Amazon displays it directly in Seller Central:

1. Log in to Seller Central and navigate to Advertising > Campaign Manager.
2. Select any active campaign to view its performance dashboard.
3. The ACOS column appears in the campaign table alongside Impressions, Clicks, Spend, and Sales.
4. Use date range filters to view ACOS for specific periods (7 days, 30 days, custom).
5. For downloadable reports, go to Advertising Reports and create a Campaign Performance or Search Term report.

Amazon calculates ACOS using the same formula shown above. The platform uses a standard attribution window (typically 7 days for clicks and 14 days for conversions under the “Last Touch” model).

If you want to understand how ACOS compares to ROAS, check our guide on ACOS vs ROAS differences.

5. Using ACOS to Make Decisions

Knowing your ACOS is only useful if you act on it. Here is how to turn ACOS data into campaign improvements:

Compare ACOS to Your Profit Margin

The golden rule: ACOS must be lower than your profit margin for a campaign to be profitable. If your product has a 30% margin and your ACOS is 35%, you lose 5% on every sale. Calculate your break-even ACOS as:

If your margin is 40%, any ACOS below 40% is profitable. Above 40% means you are losing money.

Adjust Bids Based on ACOS

• If ACOS is well below your target — consider raising bids to capture more traffic.
• If ACOS is above your target — lower bids, pause high-spend low-converting keywords, or improve your product listing conversion rate.

Segment by Match Type

Broad-match campaigns often have higher ACOS. Exact-match campaigns tend to have lower ACOS. Compare ACOS across match types to allocate budget efficiently. A 25% ACOS on exact match may be excellent, while 25% on broad match is harder to achieve.

Learn more about what a 25% ACOS means in terms of ROAS in our dedicated guide: 25% ACOS to ROAS conversion.

6. Frequently Asked Questions