CPA (cost per acquisition) is what you pay in ad spend for one conversion, such as a lead, a demo request or a customer. The formula is CPA = ad spend / conversions, so $12,000 for 40 demo requests is a $300 CPA. Enter any two of spend, conversions and CPA below and the calculator works out the third. Add your deal value, margin and close rate to see what a conversion is worth and the most you can pay for one.
2025 B2B cost per lead medians (Metadata, 153 B2B advertisers)
What is the CPA formula?
Cost per acquisition is ad spend divided by conversions. Turn it around to set a budget, or chain it with your close rate and deal value to see what the conversions are worth:
| To find | Formula | Example |
|---|---|---|
| CPA | Ad spend / Conversions | $12,000 / 40 = $300 |
| Ad spend (budget) | CPA x Conversions | $300 x 60 = $18,000 |
| Conversions | Ad spend / CPA | $15,000 / $300 = 50 |
| CPA from CPC | CPC / Click-to-conversion rate | $9.39 / 3% = $313 |
| Ad cost per customer | CPA / Conversion-to-customer rate | $300 / 10% = $3,000 |
| Break-even CPA | Deal value x Gross margin x Conversion-to-customer rate | $24,000 x 80% x 10% = $1,920 |
When you combine campaigns, add the spend and add the conversions before you divide. For the definition and how attribution changes the number, see our glossary entry on cost per acquisition.
What is the difference between CPA and CAC?
CPA and CAC both divide a cost by a result, but they answer different questions. CPA is a campaign metric: ad spend for one conversion event. CAC is a business metric: the full cost of winning a new customer.
| CPA (cost per acquisition) | CAC (customer acquisition cost) | |
|---|---|---|
| Cost included | Ad spend for a channel or campaign | All sales and marketing: salaries, tools, agencies, events and media |
| Result counted | Any conversion you choose: lead, demo request, trial, customer | New paying customers only |
| Who uses it | Campaign managers, daily or weekly | Founders, finance and the board, quarterly |
| Typical use | Bids, budgets and creative decisions | Payback, LTV:CAC and how much to invest in growth |
Illustrative, not a benchmark. Brightquay, a fictional payroll software company, spends $12,000 on LinkedIn and Google in a quarter and gets 40 demo requests: a $300 CPA. Four of them become customers, so the ads cost $3,000 per customer. Across the whole company, Brightquay spent $90,000 on sales and marketing that quarter, including two salespeople and its tools, and won 12 new customers from all channels: a $7,500 CAC. All three numbers are right; they measure different things. To work out the full figure for your company, use the CAC calculator.
What is a good CPA for B2B ads?
A good CPA is one well below your break-even CPA, the gross profit one conversion is worth. Published benchmarks help you sanity-check the first step. Metadata's 2026 B2B Paid Media Benchmark ($57.6 million of 2025 spend across 153 B2B advertisers) reports these medians across advertisers:
| Channel | Median cost per lead | Median CPC | Advertisers |
|---|---|---|---|
| Google Ads | $524 | $9.76 | 56 |
| $202 | $9.39 | 138 | |
| $145 | $1.95 | 71 | |
| $138 | $2.82 | 49 |
Source: Metadata, "What LinkedIn Ads Cost in 2025", medians across advertisers for 2025 campaigns, re-checked on 30 October 2026.
The same report goes further down the funnel for advertisers with a connected CRM. LinkedIn cost $58,572 per customer, against $31,939 across the whole dataset, and LinkedIn lead gen forms cost $193 a lead against $346 for landing page campaigns. A cheap lead is not a cheap customer, which is why the calculator adds your close rate and deal value.
How do you set a target CPA?
Start from what a conversion is worth and work down.
- Work out the break-even CPA. Deal value x gross margin x the share of conversions that close. Above it, the ads lose money in the first year.
- Leave room for everything else. Ad spend is only part of CAC. Salaries, tools and agency fees come out of the same gross profit, so most teams set the target CPA at a fraction of break-even.
- Optimize for the right conversion. With Google's Target CPA bidding, the bid strategy chases the conversion you give it. Give it a qualified demo request or an SQL, not a content download, or it will find you cheap actions that never close.
- Lower CPA with conversion rate, not only bids. CPA = CPC / conversion rate, so a landing page that converts 4% instead of 3% cuts CPA by a quarter at the same CPC. Track each stage with our conversion rate calculator.
How does CPA connect to CPC, CTR and ROAS?
- Click cost. CPA = CPC / click-to-conversion rate. Work out the click side with our CPC calculator and the CTR calculator.
- Return. The "revenue per $1 of ads" figure in the calculator is a first-year ROAS on closed deals. The ROAS calculator adds pipeline and a break-even ROAS.
- Lead cost. When the conversion is a form fill, CPA is your cost per lead.
If you want help bringing CPA down, our paid ads service runs Google and LinkedIn campaigns for B2B SaaS, feeds the ad platforms the conversions that turn into pipeline, and reports cost per opportunity next to CPA every week.
Frequently asked
How do you calculate CPA?
Divide ad spend by the number of conversions it produced. CPA = spend / conversions. $12,000 of ad spend that produced 40 demo requests is a $300 CPA. Use spend and conversions from the same campaigns and dates, and say which conversion you count (lead, demo request, trial or customer).
What is the difference between CPA and CAC?
CPA is ad spend divided by one conversion event, usually for one channel or campaign. CAC is everything you spend on sales and marketing (salaries, tools, agencies and media) divided by new customers. A $300 CPA per demo request and a $7,500 CAC can describe the same company in the same quarter. Use CPA to run campaigns and CAC to judge the whole go-to-market.
What is a good CPA for B2B?
One that is well below your break-even CPA: the gross profit a conversion is worth. As a reference for cost per lead, Metadata's 2025 B2B medians are $202 on LinkedIn, $524 on Google Ads, $145 on Facebook and $138 on Instagram. A $500 cost per lead can be good for a $50,000 contract and ruinous for a $3,000 one, so set the target from your own numbers.
How do you calculate break-even CPA?
Break-even CPA = average deal value x gross margin x the share of conversions that become customers. With a $24,000 first-year contract, 80% gross margin and 10% of demo requests closing, each demo request is worth $1,920 of gross profit, so any CPA under $1,920 pays back in the first year.
Is CPA the same as cost per lead?
Cost per lead is a CPA where the conversion is a lead. CPA is the general term: the conversion can be a lead, a demo request, a trial sign-up or a paying customer. Always name the conversion, because a $200 CPA per lead and a $200 CPA per customer are very different results.
What is target CPA in Google Ads?
Target CPA is an automated bid strategy: you set the average cost per conversion you want, and Google Ads sets bids to get as many conversions as possible at that average. Google recommends a target from your last 30 days of conversions. Feed it the conversion that matters (a qualified demo request, not a page view), or it will optimize for cheap, low-value actions.
