ROI to ROAS Calculator

Turn ROI into ROAS—or ROAS into ROI—with the total cost and ad spend behind each number. When those costs differ, one ratio alone cannot pick a single answer.

100% Free
Two-way converter
Updates as you type
Cost assumption

Default. Enter total cost for ROI and ad spend for ROAS so the tool can restore implied revenue.

Conversion direction
%

Enter ROI as a percentage. -100% means zero revenue.

$

Include every cost used in your ROI calculation.

$

Enter only the ad spend used as the ROAS denominator.

Conversion result

Conversion result: 50% converts to 6×.

Input

50%

Converted value

Implied revenue

$1,200

Formula

Implied revenue = total cost × (1 + ROI ÷ 100) = $800 × (1 + 50 ÷ 100) = $1,200.

ROAS = implied revenue ÷ ad spend = $1,200 ÷ $200 = 6×.

ROI to ROAS example

Why can the same 50% ROI become 6× or 3× ROAS?

The 6× above is this setup with $200 in ad spend. Keep ROI at 50% and total cost at $800—implied revenue stays $1,200. Change only the ad-spend share, and ROAS flips.

Restore revenue from ROI and total cost, then divide by each scenario's ad spend.

ROI

50%

Total cost

$800

Implied revenue

$1,200

$800 × (1 + 50%)

Then divide by ad spend

The denominator changes by scenario.

Scenario A: lower ad-spend share

$1,200 ÷ $200

6× ROAS

Scenario B: higher ad-spend share

$1,200 ÷ $400

3× ROAS

What stayed the same?

ROI stays at 50% because its top and bottom use the same total cost. ROAS changes because the ad-spend denominator changes.

The rule: You need the total-cost and ad-spend relationship. A ratio alone cannot choose one ROAS when those amounts can differ.

What this example leaves out

  • This is hypothetical, not a customer result or public-user data.
  • It depends on the total cost you supply; it cannot find costs that were omitted.
  • It does not fix attribution gaps, mixed reporting windows, or different conversion-value rules.

Before you convert

What has to match before you convert?

Enter total cost and ad spend from the same campaign, period, currency, and conversion-value definition.

Total cost: every cost that went into your ROI—not just ads.
Ad spend: only the advertising cost used as the ROAS denominator.
Quick mode: use it only after confirming ad spend was the entire ROI cost.

ROI and ROAS formula

How do you convert ROI to ROAS?

When total cost and ad spend differ, restore implied revenue first. Then apply each metric's own denominator.

ROI = (revenue − total cost) ÷ total cost × 100. Enter ROI as a percentage (for example, 50%).
ROAS = attributed revenue ÷ ad spend. Enter ROAS as a multiplier (for example, 1.5×).
Shortcut only when ad spend is the entire ROI cost: ROAS = (ROI ÷ 100) + 1, or ROI = (ROAS − 1) × 100.

Quick lookup

What if ad spend is the only cost?

Use this table only when ad spend is the entire cost in the ROI calculation. If total cost includes more, enter both amounts in the calculator instead.

ROIROAS
0%
50%1.5×
100%
200%
300%
400%

Shortcut: ROAS = (ROI ÷ 100) + 1 when ad spend is the full ROI cost.

Common mistakes

What can a ROI to ROAS conversion not tell you?

Common errors

  • Treating ROI and ROAS as interchangeable without checking their denominators.
  • Mixing revenue, spend, or costs from different dates, currencies, campaigns, or attribution windows.
  • Using a ratio-only shortcut when total cost includes more than ad spend.

What this result cannot decide

  • It cannot prove profitability—omitted costs and conversion value can change that call.
  • It cannot fix attribution uncertainty or recover costs you did not supply.
  • It cannot produce one unique conversion from ROI or ROAS alone when total cost and ad spend are not known to match.

Sources

Where do these ROI and ROAS definitions come from?

This calculator uses ROI with total cost and ROAS with ad spend. The shortcut appears only as a confirmed special case.

ROI (return on investment)

Google Ads describes ROI as net profit relative to costs—roughly revenue minus total costs, divided by total costs. What counts as cost depends on your goal.

Google Ads: About return on investment

ROAS (return on ad spend)

Google Ads defines ROAS as total conversion value divided by total spend. That value may be sales revenue, margin, or another tracked amount.

Google Ads: ROAS glossary entry

What these definitions do not settle

They guide the math. They do not standardize your attribution model, cost ledger, or conversion-value policy.

Last reviewed

August 1, 2026. Recheck the linked source and your reporting definitions before using a result for a business decision.

ROI to ROAS conversion FAQ

Next move

What should you do next?

Have attributed revenue and ad spend? Calculate ROAS directly. Need the difference between the two metrics, not a converted ratio? Read ROAS vs ROI.

Useful next steps

ROAS Calculator

Calculate ad-attributed revenue divided by ad spend

ROAS vs ROI

When you needed the difference, not a converted ratio