Retargeting Budget Calculator
A retargeting budget is capped by how many people have already visited your site. This calculator starts there: the audience you can reach, the impressions your chosen frequency implies, what they cost, and whether the campaign pays for itself on your margin.
Starts from your site traffic: how many people you can reach, how many impressions your frequency implies and what that costs. Starting values (CPM, CTR and conversion included) are examples only — use your own ad account's numbers.
Monthly retargeting budget
823
On these numbers the spend exceeds the contribution it brings: 280 lost per month.
The numbers you enter stay in your browser and are never sent to a server.
How it's calculated
Audience = monthly visitors × (membership days ÷ 30) × reachable share. A longer window grows the pool; the reachable share removes people lost to consent and matching.
Impressions = audience × weekly frequency × (30 ÷ 7). Budget = impressions ÷ 1,000 × CPM. Frequency is the real budget dial: double it on the same audience and the spend doubles.
Orders = impressions × CTR × conversion rate. Their contribution is set against the spend, and the tool shows the highest CPM the campaign can pay without losing money.
What people most often forget
- Attribution isn't lift. A cart abandoner might have returned anyway. Part of what the platform reports would have happened without the ad; a hold-out test shows the real effect.
- Exclude buyers. Showing the same product to someone who already ordered wastes budget; add purchasers as an exclusion.
- Segment by intent. An add-to-cart visitor and a homepage bouncer aren't worth the same; one bid and frequency for both drags the average down.
- Consent shrinks the pool. Visitors who decline may never join the audience; plan on the audience size your ad account reports, not raw traffic.
Scope, sources and freshness
A planning tool: CPM, CTR and conversion are your assumptions and vary by platform, creative, season and competition. It connects to no ad account. Brand effects, multi-touch attribution and lifetime value are out of scope. Starting values are examples only; keep all amounts in one currency.
Sources last reviewed: 14 October 2026
Frequently asked
How do I calculate a retargeting budget?
Find the reachable audience (monthly visitors × window ÷ 30 × reachable share), multiply by weekly frequency to get monthly impressions, then budget = impressions ÷ 1,000 × CPM. The audience caps the budget: spending more usually means showing the same people more often.
What frequency is right for retargeting?
There's no universal number. Test two levels and compare extra orders per extra impression; once frequency rises and orders don't, the added spend is just repeating to the same people.
How do I find the highest CPM I can afford?
Divide the total contribution of the orders the campaign brings by thousands of impressions. Above that CPM the campaign loses money; the calculator does this from your inputs.
Can I trust the ROAS the platform reports?
Not directly. Some retargeted people would have bought anyway, so attributed sales can exceed the real lift. Holding part of the audience out and comparing conversion between groups measures it.
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