Paid ads calculator

Google Ads ROI Calculator

Google Ads reports media performance, while a profitability decision also needs conversion value, margin, and the cost of managing the program. This calculator starts with clicks and conversion rate, making the relationship between traffic quality, CPA, revenue, and profit visible.

Reviewed Jul 22, 2026

Your assumptions

Currency

Google Ads spend

Media spend for the selected period.Clicks

Valid clicks associated with the spend.Conversion rate

Conversions divided by clicks.Average conversion value

Revenue value per conversion.Gross margin

Margin after product or service delivery.Management and creative cost

Agency, internal labor, creative, and landing pages.

Estimated result

Google Ads ROI

40%

Estimated attributed revenue is $28,000.

Revenue ROAS: 2.8:1
Media cost per acquisition: $50
Estimated revenue: $28,000

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Transparent math

How the calculation works

Google Ads ROI = (Clicks × Conversion rate × Order value × Margin − Spend − Management cost) ÷ Total cost

Clicks multiplied by conversion rate estimate conversions. Conversions multiplied by average value estimate attributed revenue. ROAS compares that revenue with media spend. ROI applies gross margin to revenue, subtracts media and management costs, and divides the remaining contribution by total campaign cost.

Worked example

Put the result in context

A campaign spends $10,000 for 5,000 clicks, converts 4%, and produces $140 per conversion. Estimated revenue is $28,000 and media ROAS is 2.8:1. At 60% margin and $2,000 of management cost, contribution after campaign cost is $4,800 and ROI is 40%.

Methodology

Make the estimate defensible

01Use conversion actions that represent business value and assign defensible values.
02Separate brand and non-brand economics before shifting budget.
03Reconcile platform-reported revenue with analytics, CRM, or transaction data.

Interpretation

What counts as a good result?

Targets should differ by campaign intent, margin, customer value, and attribution confidence. Brand search, shopping, non-brand search, and remarketing should not share one performance threshold. Compare conversion values imported to Google Ads with backend revenue and refund data.

Read before deciding

Limitations

The calculator assumes one average conversion rate and value across all clicks.
Offline conversions, refunds, repeat purchases, and assisted conversions require additional modeling.
CPA shown here uses media spend only; ROI includes management cost.

Common questions

Frequently asked questions

Why is Google Ads ROI lower than ROAS?

ROAS uses revenue and media spend. ROI applies margin and subtracts additional campaign costs, so it is a stricter profitability measure.

Should brand search be included?

Report it separately. Brand campaigns often capture demand created elsewhere and can make total account performance look stronger.

How should lead-generation conversion value be set?

Use lead-to-customer rate multiplied by expected contribution per customer, ideally segmented by lead type or campaign.

Does CPA include agency fees?

The CPA output uses ad spend divided by conversions. For a fully loaded acquisition cost, add management and other costs to the numerator.

Sources and further reading

Continue the analysis