Calculate advertising cost of sales, estimate the ad spend supported by your revenue, determine the revenue required for a target ACOS, or convert between ACOS and ROAS. All calculations run locally in your browser.
Calculate ACOS
Calculate advertising cost of sales, reverse-calculate cost or revenue, and convert between ACOS and ROAS.
Advertising cost of sales
25%
- ACOS
- 25%
- Equivalent ROAS
- 400% (4x)
- Advertising cost
- $2,500.00
- Advertising revenue
- $10,000.00
- Cost per 100 in revenue
- $25.00
- Revenue per 1 spent
- $4.00
Recent calculations
ACOS and ROAS use attributed revenue, not profit. Currency options change display formatting only and do not convert exchange rates.
What Is ACOS?
ACOS stands for advertising cost of sales. It measures advertising cost as a percentage of the sales revenue attributed to advertising.
The standard formula is:
ACOS = Advertising Cost ÷ Advertising Revenue × 100
Suppose an advertising campaign costs $2,500 and generates $10,000 in attributed sales:
ACOS = $2,500 ÷ $10,000 × 100
ACOS = 25%
A 25% ACOS means that $25 was spent on advertising for every $100 in attributed advertising revenue.
ACOS is commonly associated with ecommerce and marketplace advertising, particularly Amazon Ads. It can also be used for other advertising channels when both advertising cost and attributed revenue are available.
How to Use the ACOS Calculator
The calculator supports five calculation modes.
Calculate ACOS
Select ACOS from ad cost and revenue when you know:
- Advertising cost
- Advertising revenue
Enter both values and select Calculate ACOS.
The result includes:
- ACOS percentage
- Equivalent ROAS percentage
- ROAS multiple
- Advertising cost
- Advertising revenue
- Cost per 100 in revenue
- Revenue generated per 1 spent
Calculate Advertising Cost
Select Ad cost from revenue and ACOS when you know:
- Advertising revenue
- Target ACOS
This mode calculates the advertising cost represented by the selected ACOS.
For example, if advertising revenue is $10,000 and target ACOS is 25%:
Advertising Cost = $10,000 × 25 ÷ 100
Advertising Cost = $2,500
Calculate Required Revenue
Select Required revenue from ad cost and ACOS when you know:
- Advertising cost
- Target ACOS
This mode calculates how much attributed revenue is required to reach the target ACOS.
For example, if advertising cost is $2,500 and target ACOS is 20%:
Required Revenue = $2,500 ÷ 20 × 100
Required Revenue = $12,500
Convert ACOS to ROAS
Select ROAS from ACOS to convert an ACOS percentage into its equivalent ROAS.
For example:
ROAS = 10,000 ÷ 20
ROAS = 500%
A 20% ACOS is equivalent to a 500% or 5.00x ROAS.
Convert ROAS to ACOS
Select ACOS from ROAS to convert a ROAS percentage into its equivalent ACOS.
For example:
ACOS = 10,000 ÷ 400
ACOS = 25%
A 400% ROAS is equivalent to a 25% ACOS.
ACOS Formula
The standard ACOS formula is:
ACOS = Advertising Cost ÷ Advertising Revenue × 100
Where:
- Advertising cost is the amount spent on the advertisement or campaign.
- Advertising revenue is the sales revenue attributed to that advertising.
- Multiplying by 100 converts the decimal result into a percentage.
If advertising cost is $600 and attributed revenue is $3,000:
ACOS = $600 ÷ $3,000 × 100
ACOS = 20%
This means advertising cost represents 20% of attributed revenue.
Advertising Cost Formula
When advertising revenue and ACOS are known, calculate advertising cost with:
Advertising Cost = Advertising Revenue × ACOS ÷ 100
Suppose:
- Advertising revenue: $40,000
- ACOS: 15%
The calculation is:
Advertising Cost = $40,000 × 15 ÷ 100
Advertising Cost = $6,000
Advertising cost of $6,000 represents 15% of $40,000 in attributed revenue.
Required Revenue Formula
When advertising cost and target ACOS are known, calculate required revenue with:
Required Revenue = Advertising Cost ÷ Target ACOS × 100
Suppose:
- Advertising cost: $4,000
- Target ACOS: 25%
The calculation is:
Required Revenue = $4,000 ÷ 25 × 100
Required Revenue = $16,000
The campaign needs $16,000 in attributed revenue for $4,000 in advertising cost to represent a 25% ACOS.
This calculation describes the mathematical relationship between the values. It does not guarantee that spending $4,000 will generate $16,000 in revenue.
ACOS Calculation Examples
Amazon Ads campaign example
A Sponsored Products campaign spends $1,200 and generates $6,000 in attributed sales.
ACOS = $1,200 ÷ $6,000 × 100
ACOS = 20%
The campaign spent $20 on advertising for every $100 in attributed sales.
Its equivalent ROAS is:
ROAS = $6,000 ÷ $1,200 × 100
ROAS = 500%
High-ACOS example
A campaign costs $4,000 and produces $5,000 in attributed sales.
ACOS = $4,000 ÷ $5,000 × 100
ACOS = 80%
Advertising consumed the equivalent of $80 for every $100 in attributed sales.
Whether this result is profitable depends on the product’s margin and other costs.
ACOS above 100%
A campaign costs $3,000 and produces $2,000 in attributed sales.
ACOS = $3,000 ÷ $2,000 × 100
ACOS = 150%
An ACOS above 100% is mathematically possible. It means advertising cost is higher than attributed revenue.
The equivalent ROAS is:
ROAS = $2,000 ÷ $3,000 × 100
ROAS ≈ 66.67%
Decimal-value example
A campaign costs $387.25 and produces $1,749.80 in attributed revenue.
ACOS = $387.25 ÷ $1,749.80 × 100
ACOS ≈ 22.13%
Use the original values for calculation and round only the displayed result.
ACOS and ROAS
ACOS and ROAS measure the same advertising cost and attributed revenue from opposite directions.
The ACOS formula is:
ACOS = Advertising Cost ÷ Advertising Revenue × 100
The ROAS formula is:
ROAS = Advertising Revenue ÷ Advertising Cost × 100
As ACOS decreases, ROAS increases. As ACOS increases, ROAS decreases.
| ACOS | ROAS percentage | ROAS multiple |
|---|---|---|
| 10% | 1,000% | 10.00x |
| 15% | 666.67% | 6.67x |
| 20% | 500% | 5.00x |
| 25% | 400% | 4.00x |
| 30% | 333.33% | 3.33x |
| 40% | 250% | 2.50x |
| 50% | 200% | 2.00x |
| 75% | 133.33% | 1.33x |
| 100% | 100% | 1.00x |
To convert ACOS to ROAS:
ROAS Percentage = 10,000 ÷ ACOS Percentage
To convert ROAS to ACOS:
ACOS Percentage = 10,000 ÷ ROAS Percentage
For a detailed explanation of return on ad spend, use the ROAS Calculator or read the ROAS formula guide.
What Is Break-Even ACOS?
Break-even ACOS is the advertising cost percentage at which the contribution generated by a sale is fully consumed by advertising cost.
Under a simplified calculation, break-even ACOS is equal to the contribution margin before advertising.
Suppose a product sells for $100 and has the following variable costs:
- Product cost: $40
- Marketplace and payment fees: $15
- Fulfillment: $10
- Other variable costs: $5
Total variable costs before advertising are:
$40 + $15 + $10 + $5 = $70
The contribution before advertising is:
$100 − $70 = $30
The contribution margin is:
$30 ÷ $100 × 100 = 30%
The simplified break-even ACOS is therefore:
30%
At a 30% ACOS, advertising costs $30 for every $100 in attributed sales. This uses the full $30 contribution available before advertising.
If ACOS is below 30%, the sale may produce a positive contribution after advertising under these assumptions. If ACOS is above 30%, the advertising cost exceeds the available contribution.
This simplified calculation does not automatically include fixed expenses, taxes, delayed costs, or customer lifetime value.
Break-Even ACOS and Break-Even ROAS
Because ACOS and ROAS are inverse measurements, a break-even ACOS can be converted into a break-even ROAS.
If the break-even ACOS is 30%:
Break-Even ROAS = 10,000 ÷ 30
Break-Even ROAS ≈ 333.33%
The same business threshold can therefore be expressed as:
- 30% break-even ACOS
- 333.33% break-even ROAS
- Approximately 3.33x break-even ROAS
If the contribution margin is 20%:
- Break-even ACOS: 20%
- Break-even ROAS: 500%
- Break-even multiple: 5.00x
| Contribution margin | Break-even ACOS | Break-even ROAS |
| 10% | 10% | 1,000% |
| 20% | 20% | 500% |
| 25% | 25% | 400% |
| 30% | 30% | 333.33% |
| 40% | 40% | 250% |
| 50% | 50% | 200% |
The margin must be calculated using a consistent cost definition.
What Is a Good ACOS?
There is no universal ACOS that is good for every advertiser.
A useful target depends on:
- Product margin
- Marketplace fees
- Payment fees
- Fulfillment costs
- Shipping costs
- Discounts
- Refunds and returns
- Advertising objective
- Product lifecycle
- Organic ranking strategy
- Repeat purchase behavior
- Customer lifetime value
- Cash-flow requirements
- Attribution methodology
A 25% ACOS may be profitable for a product with a 50% contribution margin before advertising. The same ACOS may be unprofitable for a product with a 15% margin.
A lower ACOS usually means less advertising cost relative to attributed sales, but the lowest possible ACOS is not always the best business objective.
A campaign with a very low ACOS may have limited advertising delivery and low total sales. A campaign with a moderately higher ACOS may generate more total contribution, reach new customers, or support a product launch.
Evaluate both efficiency and scale.
Target ACOS by Campaign Objective
The appropriate ACOS target may change according to the advertising objective.
Profit-focused campaigns
A profit-focused campaign usually needs an ACOS below the product’s break-even threshold.
The target should leave enough contribution to cover fixed costs and produce the desired profit.
Product-launch campaigns
A new product campaign may temporarily accept a higher ACOS to:
- Generate initial sales
- Collect performance data
- Test keywords
- Build visibility
- Reach new customers
- Support organic discovery
A higher ACOS still needs a defined limit and review period.
Brand-awareness campaigns
ACOS may not be the primary performance metric for campaigns focused on awareness.
Relevant supporting metrics may include:
- Reach
- Impressions
- Video views
- New-to-brand customers
- Branded searches
- Detail-page views
Growth-focused campaigns
A growth campaign may accept a higher first-purchase ACOS when repeat purchases are reliably measured.
Avoid assuming future customer value without sufficient historical evidence.
ACOS vs. TACOS
ACOS commonly compares advertising cost with advertising-attributed sales.
TACOS, often called total advertising cost of sales, compares advertising cost with total sales.
The common formula is:
TACOS = Advertising Cost ÷ Total Sales × 100
Suppose:
- Advertising cost: $5,000
- Advertising-attributed sales: $20,000
- Total sales: $50,000
ACOS is:
$5,000 ÷ $20,000 × 100 = 25%
TACOS is:
$5,000 ÷ $50,000 × 100 = 10%
The two metrics answer different questions.
ACOS focuses on the efficiency of attributed advertising sales. TACOS places advertising cost in the context of total business or product sales.
Do not compare ACOS and TACOS without labeling them.
ACOS vs. ROI
ACOS measures advertising cost relative to attributed revenue.
ROI generally evaluates net return relative to an investment.
A campaign can have a low ACOS but still produce weak business returns if:
- Product costs are high
- Fulfillment is expensive
- Refund rates are high
- Discounts reduce margins
- Agency and creative costs are excluded
- The attributed revenue is overstated
ACOS is a useful advertising-efficiency metric, but it is not a complete profitability calculation.
ACOS vs. CPA
CPA measures the average advertising cost per conversion or acquisition.
CPA = Advertising Cost ÷ Conversions
ACOS measures advertising cost relative to revenue.
Suppose:
- Advertising cost: $2,000
- Conversions: 100
- Attributed revenue: $8,000
CPA is:
$2,000 ÷ 100 = $20
ACOS is:
$2,000 ÷ $8,000 × 100 = 25%
CPA shows that each conversion costs an average of $20. ACOS shows that advertising consumed 25% of attributed revenue.
Two campaigns can have identical CPA values but different ACOS values when their average order values differ.
ACOS vs. Conversion Rate
Conversion rate measures how frequently clicks, visitors, or sessions produce conversions.
ACOS measures advertising cost relative to attributed revenue.
A high conversion rate does not guarantee a low ACOS. Clicks may be expensive or conversion values may be low.
A lower conversion rate can still produce an acceptable ACOS if successful conversions have high values.
Use the Conversion Rate Calculator to measure conversions separately.
What Counts as Advertising Revenue?
Use revenue attributed to the advertising scope being measured.
Depending on the platform and campaign, this may include:
- Sales of the advertised product
- Sales of related products
- Brand-level attributed sales
- Purchases recorded within an attribution window
- Imported or offline sales
The exact definition can vary by campaign and account type.
Attributed advertising revenue may not equal the sales shown in a retail, ecommerce, or accounting report because the systems can use different:
- Attribution rules
- Reporting dates
- Time zones
- Refund handling
- Product scopes
- Order-status rules
- Customer identifiers
Record the source of the revenue used in the calculation.
What Counts as Advertising Cost?
A platform ACOS calculation generally uses the media spend recorded by the advertising platform.
A broader business analysis may include:
- Media spend
- Agency fees
- Creative production
- Freelance services
- Advertising software
- Campaign management labor
- Tracking systems
- Other campaign expenses
If additional expenses are included, document them clearly. A platform ACOS based only on media spend should not be compared directly with a broader ACOS calculation that includes agency and production costs.
How to Calculate Combined ACOS
Do not calculate an overall ACOS by taking a simple average of campaign percentages when campaigns have different revenue amounts.
Suppose:
| Campaign | Advertising cost | Revenue | ACOS |
| Campaign A | $100 | $1,000 | 10% |
| Campaign B | $2,000 | $5,000 | 40% |
A simple average gives:
(10% + 40%) ÷ 2 = 25%
However, the campaigns have different revenue amounts.
Add cost and revenue first:
Total Advertising Cost = $100 + $2,000 = $2,100
Total Revenue = $1,000 + $5,000 = $6,000
Then calculate combined ACOS:
Combined ACOS = $2,100 ÷ $6,000 × 100
Combined ACOS = 35%
The weighted combined ACOS is 35%, not 25%.
Why ACOS Changes Over Time
ACOS may change because of:
- Advertising cost
- Click costs
- Conversion rate
- Average order value
- Product price
- Discounts
- Competition
- Search demand
- Inventory
- Buy Box eligibility
- Seasonality
- Attribution delays
- Refunds and cancellations
- Campaign targeting
- Creative performance
A change in ACOS does not identify the cause by itself. Review the underlying cost, clicks, conversions, orders, revenue, and product data.
Recent reports may also be incomplete when attributed purchases occur after the advertising click or view.
How to Reduce ACOS
Reducing ACOS requires decreasing advertising cost relative to attributed revenue.
Possible actions include:
- Improve keyword and product targeting
- Add irrelevant queries as negative targets
- Adjust bids using sufficient data
- Improve product-page quality
- Maintain accurate product information
- Improve pricing competitiveness
- Review inventory availability
- Improve conversion rate
- Test advertising creative
- Separate branded and non-branded traffic
- Review performance by placement
- Move budget toward reliable targets
- Pause wasteful targeting after sufficient evaluation
- Improve measurement and attribution consistency
Do not reduce bids solely to produce a lower ACOS. Excessive bid reductions may reduce impressions, clicks, sales, and total contribution.
The objective should be an appropriate balance between efficiency, sales volume, and business goals.
Common ACOS Calculation Mistakes
Reversing the formula
Advertising revenue divided by advertising cost calculates ROAS, not ACOS.
Using total sales instead of attributed sales
Advertising cost divided by total sales generally produces a TACOS-style metric.
Treating ACOS as profit margin
ACOS only describes advertising cost relative to attributed revenue.
Ignoring other costs
A low ACOS does not guarantee profitability when product and operating costs are high.
Mixing currencies
Advertising cost and revenue must use the same currency.
Comparing different attribution settings
Campaign reports using different attribution windows may produce different ACOS values.
Averaging percentages
Combine advertising cost and revenue before calculating an overall ACOS.
Ignoring reporting delays
Recent campaigns may not yet include all attributed sales.
Using a universal target
Target ACOS should reflect the product’s margin and campaign objective.
Calculation Accuracy and Privacy
The OutputMath ACOS Calculator performs calculations locally in your browser.
The calculator:
- Does not require an account
- Does not send entered values to an external calculation server
- Supports decimal values
- Calculates ACOS and reverse values
- Converts between ACOS and ROAS
- Supports multiple currency display formats
- Stores up to five recent calculations in browser storage
- Creates optional share URLs containing calculation values
The currency selector changes formatting only. It does not convert currencies using exchange rates.
Results depend entirely on the entered values. Confirm your revenue attribution, advertising cost, margins, reporting period, and business assumptions before making budget decisions.
Frequently Asked Questions
What is the ACOS formula?
The standard formula is:
ACOS = Advertising Cost ÷ Advertising Revenue × 100
What does 25% ACOS mean?
A 25% ACOS means $25 was spent on advertising for every $100 in attributed advertising revenue.
Is a lower ACOS always better?
A lower ACOS indicates less advertising cost relative to attributed revenue. However, an extremely restrictive target may reduce advertising delivery and total sales.
Can ACOS exceed 100%?
Yes. ACOS exceeds 100% when advertising cost is greater than attributed revenue.
Can ACOS be zero?
ACOS is 0% when advertising cost is zero and attributed revenue is greater than zero. ACOS cannot be calculated when attributed revenue is zero because division by zero is undefined.
What is the difference between ACOS and ROAS?
ACOS divides advertising cost by attributed revenue. ROAS divides attributed revenue by advertising cost.
What ROAS equals 20% ACOS?
A 20% ACOS is equivalent to 500% or 5.00x ROAS.
What ACOS equals 400% ROAS?
A 400% ROAS is equivalent to 25% ACOS.
Is break-even ACOS equal to profit margin?
Under a simplified model, break-even ACOS may equal the contribution margin available before advertising. The result depends on which costs are included in that margin.
Is ACOS the same as TACOS?
No. ACOS normally uses advertising-attributed sales. TACOS uses total sales.
Does the currency change the ACOS percentage?
No. The result is unchanged when cost and revenue use the same currency. The selector only changes monetary formatting.
How do I calculate required revenue?
Use:
Required Revenue = Advertising Cost ÷ Target ACOS × 100
How do I calculate advertising cost from ACOS?
Use:
Advertising Cost = Advertising Revenue × ACOS ÷ 100
Related Advertising Calculators
Use these related tools to evaluate advertising performance:
- ROAS Calculator for attributed revenue relative to advertising cost
- CPC Calculator for average cost per click
- CPM Calculator for advertising cost per 1,000 impressions
- CTR Calculator for clicks relative to impressions
- Conversion Rate Calculator for conversions relative to clicks or visitors
Learn More About ACOS
Need help setting a target ACOS, calculating break-even ACOS, or comparing ACOS with ROAS and TACOS? Read our complete guide to calculating ACOS.