Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Max profitable spend on this pool
$4,253
Expected incremental conversions
210.0
Expected incremental revenue
$18,900
Max profitable CPC (assumes 2% CTR)
$10.63
Recommended weekly spend cap
$4,253
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How to use this
- 1Enter retargeting audience size.
- 2Enter expected conversion rate for this recency window (%).
- 3Enter average order value ($).
- 4Enter gross margin (%).
- 5Enter incrementality rate for retargeting (%).
- 6Enter target incremental roas.
- 7Read your max profitable spend on this pool on the right — it updates as you type.
- 8Hit Share to keep the scenario or send it to someone.
About this calculator
Retargeting pools decay fast: the visitor who abandoned a cart three days ago is worth far more to chase than one from six weeks ago, and most accounts overspend on stale segments because the ad platform doesn't tell you a pool's value is dropping. This calculator takes your audience size, baseline conversion rate for that recency window, average order value, and margin, then computes expected incremental revenue and the maximum cost-per-click or cost-per-thousand-impressions you can pay and stay profitable, after applying an incrementality haircut (since a meaningful share of retargeted buyers would have returned anyway). It also flags a recommended spend cap, since even a profitable CPC doesn't mean you should spend without limit — pool value depletes as you reach the same users repeatedly, which is a frequency and fatigue problem more than a targeting one. Segment your retargeting pools by recency (0-3 days, 4-14 days, 15-30 days) and run each through this separately, because blending them into one audience value estimate hides the fact that most of the real value sits in the freshest window and the older segments are often barely worth bidding on at all.
Worked example
Using the values the calculator loads with:
Inputs
- Retargeting audience size: 20000
- Expected conversion rate for this recency window: 3 %
- Average order value: 90 $
- Gross margin: 45 %
- Incrementality rate for retargeting: 35 %
- Target incremental ROAS: 2
Results
- Max profitable spend on this pool: $4,253
- Expected incremental conversions: 210
- Expected incremental revenue: $18,900
- Max profitable CPC (assumes 2% CTR): $10.63
- Recommended weekly spend cap: $4,253
What each field means
Inputs
- Retargeting audience size
- The retargeting audience size used in the calculation. Starts at 20000 so you have a working example on load.
- Expected conversion rate for this recency window (%)
- The expected conversion rate for this recency window used in the calculation, measured in %. Starts at 3 % so you have a working example on load. Accepted range: 0.1–50 %.
- Average order value ($)
- The average order value used in the calculation, measured in $. Starts at 90 $ so you have a working example on load.
- Gross margin (%)
- The gross margin used in the calculation, measured in %. Starts at 45 % so you have a working example on load. Accepted range: 1–95 %.
- Incrementality rate for retargeting (%)
- The incrementality rate for retargeting used in the calculation, measured in %. Starts at 35 % so you have a working example on load. Accepted range: 1–100 %.
- Target incremental ROAS
- The target incremental roas used in the calculation. Starts at 2 so you have a working example on load. Accepted range: 0.5–20.
Results
- Max profitable spend on this pool
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Expected incremental conversions
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Expected incremental revenue
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Max profitable CPC (assumes 2% CTR)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Recommended weekly spend cap
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why apply an incrementality haircut to retargeting specifically?
Retargeting shows ads to people who already know your brand and were often already going to return, especially cart abandoners within 24-48 hours. Studies and holdout tests commonly put retargeting incrementality between 20-50%, meaning half or more of attributed conversions would have happened without the ad.
How should I segment audiences by recency?
Split into at least three windows: 0-3 days (highest intent, highest value), 4-14 days (moderate), and 15-30+ days (low value, mostly brand-awareness territory at that point). Run this calculator separately for each since conversion rate and incrementality both drop sharply as recency window widens.
What does the max CPC assume and why might it be wrong for my account?
It assumes a 2% click-through rate to translate a spend cap into a rough CPC ceiling, which is a simplification — actual CTR varies by placement and creative. Use the max profitable spend number as your primary constraint and treat the CPC figure as directional, not a precise bid instruction.
Why cap spend even if a pool looks profitable?
Frequency caps matter more than aggregate ROAS math suggests. Hitting the same 500 people 40 times a month drives down marginal returns and increases ad fatigue and brand annoyance well before the platform-reported ROAS shows a problem.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Retargeting Audience Value Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/retargeting-audience-value-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/retargeting-audience-value-calculator" target="_blank" rel="noopener">Retargeting Audience Value Calculator — RevenueLab</a> (2026).</p>
Source: [Retargeting Audience Value Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/retargeting-audience-value-calculator) (2026).