healthy
CAC:LTV ≥ 1:3
Every dollar of acquisition returns $3+ in contribution margin over customer lifetime.
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§ · journal
Blended CAC. The honest formula.
What vendor dashboards under-report and why. The full-spend blended CAC formula, what to include and exclude, iOS 18 adjustments, and the CAC-to-LTV ratio operators actually track.
§ 01 · TL;DR
Total spend. Total customers. Divide.
Blended CAC is total acquisition spend (paid media, organic content production, tools, agency fees, commissions) divided by total new customers in the period, regardless of which channel claims credit. This is the only CAC number that survives iOS 18 attribution disruption and removes the 20 to 40 percent channel double-counting that plagues per-vendor dashboards. A brand spending $95,000 across every channel and acquiring 1,200 new customers has a blended CAC of $79. The ratio that matters is blended CAC against contribution-margin LTV, not gross revenue LTV; most brands that think they are at 1:3 are actually at 1:1.2 once margin is applied correctly.
§ 02 · the formula
Include everything. Exclude nothing.
blended CAC =
(paid media + organic production + tools + fees + commissions)
÷
total new customers
include
- Meta Ads, Google Ads, TikTok, LinkedIn spend
- Content production (video, photo, copy) costs
- Attribution + analytics tools
- Agency retainers allocated to acquisition
- Influencer + affiliate commissions
- Creative freelancer fees
- Email-tool subscription (prorated for acquisition flows)
- Landing-page build costs
exclude
- Retention spend (loyalty tools, retention email)
- Customer service costs
- Fulfillment + shipping
- Product development
- General overhead (rent, admin)
- Brand advertising with no acquisition intent
§ 03 · what the number means
CAC is not a standalone number.
A $79 blended CAC is neither good nor bad in isolation. It becomes meaningful when paired with contribution-margin LTV (the profit a customer generates over their full relationship), first-order contribution margin (whether the first purchase alone covers the acquisition cost), and payback period (how many months to recover the CAC). Use the Blended CAC calculator and LTV calculator together, not separately.
strong
CAC:LTV ≥ 1:5
Premium brand economics. Scale acquisition spend aggressively.
burning
CAC:LTV < 1:1
Losing money per customer. Fix before scaling.
§ 04 · questions
Five answers.
What is blended CAC and how do I calculate it?
Blended CAC is total acquisition spend divided by total new customers across a period, regardless of which channel drove each customer. The formula: total paid + organic + tools + fees + commissions, all divided by new customers. A brand that spent $95,000 across Meta ($60K), Google ($25K), influencer commissions ($5K), attribution tool ($2K), and affiliate fees ($3K) and acquired 1,200 new customers has a blended CAC of $79. Blended CAC is the true cost-per-new-customer because it removes channel double-counting and captures spend that per-channel ROAS misses (tools, fees, organic content production).
Why is blended CAC higher than what Meta or Google report?
Two reasons. One, every channel double-counts. Meta credits a conversion that Google also saw; Google credits a conversion TikTok also saw. Summing per-channel-reported customers overcounts by typically 20 to 40 percent. Blended CAC removes double-counting because the denominator is actual unique new customers. Two, per-channel reporting only captures that channel's spend. Tools (attribution, analytics, email), fees (agency, creative, commissions), and content production are missed. These typically add 10 to 25 percent to true CAC on top of the double-counting correction.
How did iOS 14 and iOS 18 change CAC calculation?
iOS 14 (2021) and iOS 18 (2024) progressively broke click-based attribution by restricting tracking IDFA, app tracking transparency, and email-pixel data. Meta's reported ROAS dropped 15 to 40 percent across most DTC brands overnight in 2021 because the actual conversions stopped being attributable. Blended CAC is relatively unaffected because it ignores per-channel attribution entirely; total spend and total customers are both still measurable. This is why blended CAC has become the primary metric for growth-stage DTC since 2021: it survives attribution disruption.
What is a healthy CAC-to-LTV ratio?
Standard targets. CAC-to-LTV of 1:3 or better is healthy; 1:5+ is strong; 1:1 or below is burning money. CAC payback under 12 months is healthy for DTC; under 6 months is strong; over 18 months signals either overspending or weak retention. Contribution-margin-based LTV is the denominator that matters, not gross revenue LTV. A $200 LTV at 40 percent contribution margin is $80 of actual profit to cover the CAC, not $200. Most brands that think they are at 1:3 are actually at 1:1.2 when contribution margin is applied correctly.
Should B2B SaaS use blended CAC or channel CAC?
B2B SaaS should track both but report blended. Channel CAC (cost of a specific paid channel divided by customers it attributed) is useful for channel allocation decisions. Blended CAC (full S&M spend divided by new customers) is the board-ready number because it captures sales-rep salaries, demo-prep time, and content production that channel-level math misses. SaaS blended CAC is typically 2-4x higher than marketing-channel CAC because sales motion is expensive. Ratio targets differ too: SaaS aims for CAC payback under 18-24 months at mid-market, under 12 months at SMB.
§ 05 · calculate your CAC