UA Budget Calculator for Mobile Apps (2025)

Most UA budgets are built backward.

Teams start with available capital, divide it across channels, and hope it delivers enough users to hit growth targets.

The problem: this approach optimizes for spending money, not acquiring users at sustainable economics.

A functional UA budget calculator starts with required user volume, applies realistic CPI benchmarks, factors in channel constraints, and validates against LTV thresholds.

Here's how to calculate what you should actually spend on user acquisition.

The Core Formula

The foundational equation for UA budget is simple:

Required Budget = (Target Users × Target CPI) + Experimentation Buffer

The complexity comes from determining accurate inputs for each variable.

Let's break down each component.

Step 1: Calculate Required User Volume

Your user target should derive from revenue goals, not arbitrary growth ambitions.

The calculation:

1. Set monthly or quarterly revenue target
2. Determine required paying users based on ARPU
3. Calculate total installs needed based on conversion rate

Example:

• Revenue target: $100K MRR
• ARPU: $25/month
• Required paying users: 4,000
• Install-to-paid conversion: 5%
• Required installs: 80,000
• Monthly target (quarterly ÷ 3): 26,667 installs

Your UA budget must deliver 26,667 installs per month to hit the revenue target.

Step 2: Determine Platform Mix

Not all installs cost the same. iOS and Android have different acquisition costs, user quality, and monetization profiles.

Platform allocation framework:

Distribute volume targets based on:

• Target audience distribution: Where are your ideal users?
• Monetization performance: Which platform delivers higher LTV?
• CPI efficiency: Where can you acquire users at better economics?

Example platform split:

Platform	Volume Target	CPI Benchmark	Budget Allocation
iOS	16,000 (60%)	$3.60	$57,600
Android	10,667 (40%)	$1.20	$12,800
Total	26,667	$2.64 blended	$70,400

iOS typically represents 50-65% of revenue for most app categories despite lower install volume, justifying higher budget allocation.

Step 3: Allocate Across Channels

Each acquisition channel has different cost structures, volume capacity, and user quality profiles.

2025 CPI Benchmarks by Channel:

Channel	Average CPI	Minimum Monthly Budget	Quality Score
Apple Search Ads	$1.40-$1.80	$2,000	High (intent-based)
Google App Campaigns	$2.50-$2.65	$1,500	Medium-High
Facebook/Instagram	$3.00-$4.00	$3,000	Medium (targeting-dependent)
TikTok Ads	$2.80-$2.90	$3,000	Medium (creative-dependent)
Programmatic	$1.50-$3.00	$2,000	Low-Medium (fraud risk)

Source: Business of Apps, industry benchmarks 2024-2025

Channel Budget Allocation Example

Using our $70,400 monthly budget target:

iOS Budget ($57,600):

• Apple Search Ads: $20,000 (12,500 installs at $1.60)
• Facebook/Instagram: $25,000 (6,940 installs at $3.60)
• TikTok: $12,600 (4,550 installs at $2.77)

iOS Total: 23,990 installs (target: 16,000) — over-allocated for expected waste/fraud

Android Budget ($12,800):

• Google App Campaigns: $7,000 (2,800 installs at $2.50)
• Facebook/Instagram: $5,800 (1,933 installs at $3.00)

Android Total: 4,733 installs (target: 10,667) — under-allocated, needs adjustment

This allocation reveals you can't hit Android targets at these CPIs with available budget. You'd need to either:

• Increase total budget to $95K
• Reduce Android volume targets
• Find lower-CPI Android channels (programmatic, incentivized traffic)

This is why the calculator matters: it surfaces feasibility constraints before you commit spend.

Step 4: Add Experimentation Buffer

Static channel allocations decay as competition, seasonality, and platform algorithms shift.

Reserve 10-15% of your total budget for experimentation:

• Testing new channels (Reddit, Snapchat, programmatic networks)
• Creative variations and messaging tests
• Audience expansion beyond core segments
• Seasonal or event-based campaigns

Budget with experimentation:

• Core channel allocation: $70,400
• Experimentation (15%): $10,560
• Total monthly budget: $80,960

This buffer allows you to discover new efficiency opportunities without disrupting proven channels.

Step 5: Validate Against LTV Constraints

Your calculated budget only works if it generates users you can monetize profitably.

The LTV:CAC test:

A sustainable UA budget maintains at least a 3:1 ratio of lifetime value to customer acquisition cost.

Example validation:

• Blended CPI: $2.64
• Install-to-paid conversion: 5%
• CAC (cost per paying customer): $2.64 ÷ 0.05 = $52.80
• Required LTV for 3:1 ratio: $158.40
• Actual LTV: $200

Result: Economics validate. You have $41.60 cushion per customer ($200 - $158.40).

If your LTV doesn't support a 3:1 ratio at calculated CPI, you need to either:

• Improve monetization to increase LTV
• Optimize acquisition to reduce CPI
• Improve activation/retention to boost install-to-paid conversion
• Reduce volume targets to match sustainable economics

Step 6: Account for Channel Minimums

Most channels require minimum monthly spend to generate meaningful performance data.

Minimum viable budget by channel:

• Apple Search Ads: $2,000/month
• Google App Campaigns: $1,500/month
• Facebook/Instagram: $3,000/month
• TikTok: $3,000/month
• Programmatic: $2,000/month

Testing 3 channels simultaneously requires a baseline budget of ~$8,000-$10,000 per month.

If your calculated budget falls below these thresholds, you face a strategic choice:

Option 1: Concentrate budget on 1-2 channels where you can afford meaningful tests

Option 2: Extend your testing timeline, running one channel at a time sequentially

Option 3: Focus on organic growth (ASO, content, referral) until you can fund multi-channel paid programs

Complete Budget Calculator

Here's a worked example combining all components:

Inputs:

• Revenue target: $150K MRR
• ARPU: $30/month
• Install-to-paid conversion: 8%
• Required paying users: 5,000
• Required installs: 62,500/quarter = 20,833/month
• Target LTV: $240
• Platform split: 65% iOS, 35% Android

iOS Calculation (13,542 installs):

Channel	Budget	CPI	Installs
Apple Search Ads	$18,000	$1.60	11,250
Facebook/Instagram	$20,000	$3.75	5,333
TikTok	$10,000	$2.85	3,509
iOS Total	$48,000	$2.39	20,092

Android Calculation (7,291 installs):

Channel	Budget	CPI	Installs
Google App Campaigns	$10,000	$2.55	3,922
Facebook/Instagram	$8,000	$3.00	2,667
Android Total	$18,000	$2.73	6,589

Total Core Budget: $66,000 Experimentation (15%): $9,900 Total Monthly Budget: $75,900

Blended CPI: $75,900 ÷ 26,681 = $2.84

CAC Validation:

• CAC: $2.84 ÷ 0.08 = $35.50
• LTV: $240
• LTV:CAC ratio: 6.76:1

Result: Budget is validated. You're acquiring users at healthy economics with significant margin for CPI fluctuation.

Adjusting for Geography

CPI varies significantly by market:

Geographic CPI modifiers (vs. global average):

• North America: +40% to +60%
• Western Europe: +20% to +40%
• Asia-Pacific: -20% to +10%
• Latin America: -30% to -10%
• Rest of World: -40% to -20%

If you're targeting US users exclusively, multiply benchmark CPIs by 1.4-1.6x.

Example:

• Global iOS CPI: $3.60
• US iOS CPI: $5.00-$5.75
• Budget impact for 10K installs: $36K → $50K-$57.5K

Adjusting for Category

App category significantly impacts acquisition costs:

Category CPI modifiers:

• Gaming (casual): Baseline
• Gaming (mid-core/hardcore): +30% to +80%
• Finance/Banking: +50% to +100%
• Health & Fitness: +10% to +30%
• Productivity: +20% to +40%
• Social/Dating: +40% to +70%
• E-commerce: +30% to +60%

Finance and gaming apps face the highest CPIs due to competition and user lifetime value potential.

Common Calculator Mistakes

Using blended CPI across all channels: Each channel has unique economics. Calculate channel-by-channel, then blend for totals.

Forgetting fraud and invalid traffic: Budget for 3-5% waste from fraudulent installs, bots, and accidental clicks.

Ignoring conversion rate variance: Your install-to-paid conversion will differ by channel. Apple Search Ads often converts 2-3x better than social channels.

Optimizing for cheapest CPI: Low CPI from low-quality traffic destroys unit economics. Optimize for CAC (cost per paying customer), not CPI.

Not accounting for ramp time: New channels take 2-4 weeks to optimize. Budget for learning phase inefficiency.

Final Budget Framework

Use this framework to calculate your UA budget:

1. Set user volume target based on revenue goals
2. Split by platform (iOS/Android) based on audience and LTV
3. Allocate across channels using CPI benchmarks and minimums
4. Add 10-15% experimentation buffer
5. Validate against LTV to ensure 3:1+ ratio
6. Adjust for geography and category if targeting specific markets
7. Review monthly and update based on actual performance

Your calculated budget should answer: "How much do I need to spend to acquire X users at sustainable economics?"

If the answer exceeds available capital, you have a strategic decision: raise more funding, reduce growth targets, or improve unit economics before scaling.

FAQs

What's the minimum budget needed for UA testing?

For meaningful testing, budget at least $1,500-$3,000 per channel per month. Testing 2-3 channels simultaneously requires a minimum monthly budget of $10,000-$15,000 to gather statistically significant performance data.

How do I calculate budget if I don't have historical CPI data?

Use industry benchmarks as starting points: iOS CPI averages $3.60 globally, Android $1.20. Apple Search Ads runs $1.40-$1.80, Facebook $3-$4, TikTok $2.80-$2.90. Plan for 20-30% variance until you gather your own data.

Should my UA budget include creative production costs?

Budget UA media spend and creative production separately. Allocate 10-20% of your media budget to creative production and testing. For a $50K monthly media budget, plan for $5K-$10K in creative development.

How often should I recalculate my UA budget?

Recalculate monthly based on actual CPI, conversion rates, and performance data. Update your baseline assumptions quarterly as you gather more data and market conditions shift.

What if my calculated budget exceeds available capital?

You have three options: (1) Reduce user volume targets to match sustainable budget, (2) Improve unit economics (increase LTV or reduce CPI) to make targets feasible, or (3) Raise additional capital specifically for growth investment.

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UA budget calculators work best when they're grounded in real performance data and validated against sustainable unit economics. Start with user volume targets, apply realistic CPI benchmarks, and test the result against LTV constraints.