Strategize

Channel Mix Optimizer

Where should the next $10K go?

Channel mix is the unsexiest growth lever and the one with the highest leverage. Most operators over-spend on one channel and starve another. This calculator allocates your next dollar to the channel with the lowest marginal CAC, after accounting for saturation.

~30%
Typical CAC drop from rebalancing
3-4
Channels in a healthy mix
2x
CAC rises when you exceed peak spend
90 day
Attribution window we recommend
Recommended Blended CAC After Reallocation
$0
Same budget. Better mix. Current blended CAC: $0
0%
CAC savings
0
Extra customers / mo
$0
Annual savings at current volume
Your Setup
SaaS

Loads sensible defaults for budget, spend, CAC, and saturation across all four channels.

$32,000

Everything you spend to acquire a customer. Ad spend, sales headcount, tooling, agency fees. Per month.

Channels
Paid Search
65

How quickly CAC rises as spend grows. Higher = sharper saturation. Search is usually steep (auction price inflation).

Paid Social
70

Meta and TikTok saturate fast at the audience level. Steep curve after creative fatigue kicks in.

Referral / Word of Mouth
30

Referrals scale gently. Volume is capped by customer count, but CAC stays flat for a long time.

Outbound / Sales
40

Outbound scales with rep headcount. CAC is sticky, not curved. Hiring is the bottleneck.

Recommended Reallocation
If you reallocate the same total budget
Marginal CAC equalization heuristic
Paid Search
Current $12,000
Recommended $10,500
-$1,500
Paid Social
Current $10,000
Recommended $8,500
-$1,500
Referral / WoM
Current $5,000
Recommended $8,000
+$3,000
Outbound / Sales
Current $5,000
Recommended $5,000
no change
If you reallocate as recommended, you get +18 extra customers per month for the same budget. Same spend. Better mix. Compound it over a year and you ship a category leader.
+18
customers / mo
Your Numbers
Current Blended CAC
$340
Total spend divided by total customers from all channels.
Optimized Blended CAC
$245
After reallocating to the channel with the lowest marginal CAC.
CAC Savings
28%
Drop in cost per customer with the same total budget.
Extra Customers / mo
+22
New customers per month from the optimized mix.
Channel Saturation Curves
Search Social Referral Outbound
Lowest Marginal CAC Referral

Each curve shows how CAC rises as you scale spend on that channel. The dot marks your current spend. The optimization finds the spend level where the marginal cost of the next customer is equal across all channels. That is your minimum blended CAC.

Typical CAC by Channel (Your Industry)
Industry median Your channel
Paid Search Google Ads, Microsoft Ads, retargeting
$320
Paid Social Meta, TikTok, LinkedIn, YouTube
$380
Referral / WoM Customer referral programs, partnerships
$180
Outbound / Sales SDRs, BDRs, account executives, cold email
$580
Sensitivity: what happens under different budgets and shocks?
Modeled against your current inputs
Operator Playbook
1 Marginal CAC is not average CAC. Your reported CAC averages every dollar. The next dollar you spend has a cost of its own. Optimize against the marginal, not the blended.
2 Saturation is real, and it bites earlier than you think. Most channels show diminishing returns by 60-70% of their peak spend. You can spend more, you just pay more for each customer.
3 Run a 90-day attribution window. Anything shorter under-credits referral and outbound. Anything longer under-credits search. Pick the window once, hold it for a year, then compare.
4 Pair CAC with contribution margin, never revenue. A $200 CAC against $600 contribution beats a $50 CAC against $80 contribution every time. Channels with bigger upfront friction often deliver bigger downstream margin.
5 Cut the worst channel slowly, not suddenly. Pulling a third of your budget out of one place in a single month creates compounding mix shock. Move 15-20% per month until the marginals equalize.

Free Detailed Report

Get the full reallocation map by email and SMS.

We will send you a 5-page PDF with your full saturation map, channel-by-channel marginal CAC curves, the three specific channels most likely to move your blended number, and a 30-minute strategy slot with the founder if you want one.

✓

Your channel mix report is on the way.

Check your inbox in the next 2 minutes for the PDF, and your phone for a single confirmation text. Sammy will personally reach out within 24 hours if you flagged the strategy-call option.

See What N1 Includes →

How this calculator works

What is marginal CAC and why does it matter?
Marginal CAC is the cost of acquiring the next customer, not the average cost of all the customers you already have. Average CAC tells you what happened. Marginal CAC tells you what the next dollar will do. If your blended CAC on social is $200 but the next $1,000 you spend brings in two customers, your marginal CAC on that next slice is $500. That is the number that should drive budget decisions.
How does the saturation steepness slider work?
The steepness slider controls how fast CAC climbs as you scale spend past your current level. At steepness 0, CAC stays flat (rare, usually only true for very small spend on a deep channel). At steepness 100, CAC roughly doubles when spend doubles. Most paid channels live between 60 and 75. Referral and SEO live closer to 20 to 40. We use a linear scaling model on the slope, which is conservative compared to a true logistic curve.
Where does the reallocation recommendation come from?
The optimizer runs a marginal-CAC equalization loop. It iteratively moves small amounts of budget from the channel with the highest marginal CAC to the channel with the lowest, recomputes the marginal CAC at each channel after the move, and repeats until the marginals converge within a tolerance band. The math is the same logic Google and Meta use internally to allocate bid budgets across audiences.
Should I just kill my worst channel?
Probably not all at once. If a channel shows a much higher marginal CAC than the others, the recommendation will already starve it. But killing it entirely loses the optionality of a future creative refresh or audience change that could reset the curve. Cut it back by 20-30% and watch the number. If marginal CAC stays high after the cut, then kill it.
What attribution window does this assume?
The model is window-agnostic. You feed it whatever CAC numbers you trust, and the optimizer respects your inputs. That said, we recommend a 90-day click-and-view window with first-touch credit for referral and outbound, and last-touch credit for search. Anything shorter buries referral. Anything longer buries search.
How accurate are the industry defaults?
Defaults are blended from public SaaS and ecommerce benchmark reports, major ad-platform industry benchmarks, and Nirvani's own deployment data across hundreds of SMB clients. They are medians, not means. Your actuals will vary by region, niche, and creative quality. Treat the defaults as starting points, then plug in your real numbers within 60 seconds.