Amazon ACoS Calculator
What is Advertising Cost of Sales (ACoS)?
ACoS (Advertising Cost of Sales) is an Amazon seller metric. It measures the effectiveness of your ad spend vs revenue. In simple terms, ACoS shows you how much you’re spending on ads to get $1 of revenue.
Let’s take an example. You spend $25 on ads and get $100 in sales, then your ACoS is 25%. The lower your ACoS, the more profitable your ad campaigns are.
Knowing your ACoS is the key to controlling your ad spend, profit optimization and growing your Amazon business with ease.
How to calculate ACoS?
Calculating your ACoS requires two data points:
- Total Ad Spend: The money you’ve spent on your Amazon advertising campaign.
- Total Ad Sales: The revenue generated from those ads.
After you get these two figures, insert them into the ACoS equation. It is a simple calculation that reveals a deep understanding of your campaign’s effectiveness.
The ACoS Formula
The formula for ACoS is:
ACoS (%) = (Ad Spend / Ad Sales) × 100
Let’s say:
- Ad Spend = $50
- Ad Sales = $200
Then:
ACoS = (50 / 200) × 100 = 25%
This means that for every dollar you made, you spent 25 cents. This information can help you establish performance standards, analyze campaigns, and decide on budgeting more intelligently.
What is an ACoS Calculator?
An ACoS Calculator is a quick and reliable tool that automates the ACoS formula for you. It saves you from doing the calculations by hand every time. Just provide your ad spend and ad sales to the calculator, and it gives your ACoS immediately.
The following list briefly outlines situations where this tool can be most useful:
- Comparing multiple campaigns
- Monitoring daily ad performance
- Planning bids and budgets
- Deciding whether your campaign is profitable or needs adjustment
It is indeed an indispensable tool for Amazon sellers, who need transparency and control over their ad performance.
Benefits of Using an ACoS Calculator
Using an ACoS Calculator saves time, removes guesswork, and supports data-driven decisions. Here’s why you should use one:
Quick Performance Assessment: Know your ad performance at a glance. No spreadsheets or mental math needed.
Profitability Tracking: Compare your ACoS with your profit margin to instantly see if your campaign is making or losing money.
Faster Optimization: Identify underperforming campaigns faster and adjust your strategy in real time.
Strategic Planning: Set realistic bid targets and budgets that keep you profitable while scaling.
Stress-Free Scaling: With clear numbers in front of you, you can scale your winning campaigns confidently without overspending.
What is Break-even ACoS?
Your Break-even ACoS is the ACoS value where you’re neither making nor losing money. It’s calculated based on your product’s profit margin. If your ACoS is equal to your profit margin, you’ve broken even.
Example:
If your product sells for $100 and your total cost (including product, fees, shipping, etc.) is $70, your profit margin is 30%.
So, your break-even ACoS is 30%.
Any ACoS lower than this means you’re profitable. Higher means you’re losing money on every sale.
Why Do I Want a Break-even ACoS?
Your break-even ACoS is your baseline. It helps you understand the absolute highest ACoS you can afford while still staying out of the red. Knowing this:
- Sets a clear threshold for when to cut off or adjust a campaign
- Helps you make decisions faster, especially when reviewing multiple campaigns
- Allows you to invest in awareness or visibility campaigns with controlled risk
If you’re just launching a product, you might temporarily run campaigns above break-even to build visibility. But long-term, staying below break-even ACoS is essential for profitability.
What is a Good ACoS?
The definition of a “good” ACoS depends on your goals. Here’s a general guide:
| Campaign Goal | Ideal ACoS |
| Max Profit | 10–25% |
| Break-even Awareness | 25–35% |
| Product Launch | 30–50% or more |
Factors that influence a good ACoS:
- Product price
- Competition in your niche
- Profit margin
- Your organic rank
- Seasonality
Always compare your ACoS to your break-even ACoS. If it’s lower, you’re in profit. If it’s higher, it’s time to optimize.
What Insights Can ACoS Tell You?
ACoS is more than just a number—it’s a diagnostic tool that reveals:
Campaign Efficiency: If your ACoS is increasing over time, it could mean rising competition or poor keyword targeting.
Keyword Performance: High ACoS on certain keywords might indicate they aren’t converting well—consider pausing or replacing them.
Budget Allocation: Use ACoS data to shift your budget toward high-performing, low-ACoS campaigns.
Product-Market Fit: If even your best-optimized campaigns have high ACoS, you might be facing low product demand or pricing issues.
Why Is My ACoS So High?
A high ACoS is usually a red flag. Common causes include:
- Broad or irrelevant keywords
Solution: Tighten targeting with exact match or negative keywords. - Low product conversion rate
Solution: Improve your product listing (title, images, reviews, price). - High CPC (cost-per-click)
Solution: Lower your bids or increase relevancy to reduce CPC. - Unoptimized campaigns
Solution: Segment your campaigns by match type, and monitor keyword performance. - Product not competitively priced
Solution: Reassess pricing and value proposition.
Fixing high ACoS requires diagnosing the root cause. Don’t just cut ad spend—optimize.
Should I Use RoAS or ACoS?
Both RoAS (Return on Ad Spend) and ACoS measure ad performance, but they express it differently:
| Metric | Formula | Good for |
| ACoS | Ad Spend ÷ Ad Sales | Amazon Sellers |
| RoAS | Ad Sales ÷ Ad Spend | Google, Meta, DTC Ads |
They are inverse of each other:
If ACoS = 25%, RoAS = 4 (i.e., $4 in sales for every $1 spent)
Use ACoS if you’re selling on Amazon—it’s the native metric in Amazon Seller Central. But if you’re comparing performance across platforms, knowing both can help unify your ad strategy.
Free Tool: ROAS to ACoS Calculator
How Do I Reduce ACoS?
Lowering your ACoS takes continuous testing and optimization. Here are proven ways to reduce it:
1. Optimize Keywords
- Use exact match for high-converting keywords
- Add negative keywords to eliminate waste
- Pause high-ACoS keywords
2. Improve Listing Conversion
- Upgrade product images and descriptions
- Use A+ Content and bullet points
- Get more reviews and social proof
3. Lower Bids Smartly
- Don’t pause all underperformers—reduce their bids gradually
- Let Amazon’s dynamic bidding optimize for conversions
4. Focus on Profitable Products
- Double down on campaigns with low ACoS and high ROI
- Retire or rethink advertising for low-margin items
5. Use Long-Tail Keywords
- Less competition = lower CPC = lower ACoS
6. Segment Campaigns
- Break campaigns into branded vs. non-branded
- Separate auto and manual targeting
Ready to Optimize Your ACoS?
Whether you’re launching a new product or fine-tuning your ad campaigns, understanding and controlling your ACoS is key to sustainable success on Amazon. Use the ACoS Calculator to stay on top of your ad performance, identify opportunities, and keep your profit margins healthy.