ROAS Forecasting: How to Predict Revenue Before Running a Single Ad (2025 Guide)
A complete guide to predicting returns, avoiding wasted ad spend, and scaling with confidence.
Why ROAS Forecasting Matters
Most founders launch ads blind.
They set a budget, choose an audience, publish the ad, and hope the results will be profitable.
But in 2025, ad costs are too high to rely on hope.
ROAS forecasting lets you predict your returns before spending a dollar.
Instead of guessing whether your ads will work, you can calculate:
Expected revenue
Expected conversions
Break-even points
Profit margins
Future outcomes at different budgets
This guide breaks down how to forecast ROAS step-by-step — and how to use it to eliminate guesswork from your ad strategy.
What Is ROAS Forecasting?
ROAS forecasting means predicting how much money your ads will generate for every dollar you spend.
Formula:
ROAS = Revenue ÷ Ad Spend
But when forecasting, you plug in the expected values — not the actuals.
ROAS forecasting typically uses:
Expected CPC
Expected conversion rate
Expected average order value (AOV)
Expected LTV
Planned ad budget
From there, you can project revenue and profit.
Why ROAS Forecasting Is Essential in 2025
ROAS forecasting has become mandatory because:
1. CPCs are rising across all platforms
Facebook CPC up
Google CPC up
TikTok CPC up
Reddit CPC up
Small mistakes cost far more now.
2. Ad platforms inflate “optimistic” metrics
They see conversions differently than your backend does.
Forecasting gives you realistic numbers.
3. Scaling without forecasting almost always kills margin
Going from $50/day → $200/day → $1,000/day requires modeling.
Not guessing.
4. Forecasting improves decision-making
You can instantly evaluate:
New audiences
New offers
New funnel steps
New landing pages
New budgets
Without wasting spend.
The 5 Inputs Required for ROAS Forecasting
There are only 5 variables you truly need to forecast ROAS accurately:
1. CPC (Cost Per Click)
Determines traffic cost.
The lower your CPC, the easier it is to achieve profitable ROAS.
2. Conversion Rate
Determines how many clicks convert into customers.
Most businesses underestimate how important conversion rate is when forecasting ROAS.
3. CPA (Cost Per Acquisition)
CPA = CPC ÷ Conversion Rate
This is your “cost per sale.”
If CPA > AOV → You lose money.
If CPA < AOV → You make money.
4. AOV / LTV
AOV is ideal for one-time purchases.
LTV is essential for subscriptions or recurring revenue.
Higher AOV/LTV = Higher ROAS.
5. Ad Budget
ROAS changes depending on spend.
Forecasting lets you test budgets like:
$100
$250
$500
$1,000
$5,000
…and see which generates the best ROAS.
How to Forecast ROAS (Step-by-Step)
Below is a simple 5-step process any founder can apply.
Step 1. Start With Your Estimated CPC
Pull CPC from:
Industry benchmarks
Google Keyword Planner
Competitor ads
Previous campaigns
Research reports
If unknown, use realistic ranges like:
Meta: $0.50–$1.50
TikTok: $0.20–$1.00
Google Search: $1.00–$4.00
Reddit: $0.30–$1.30+
Step 2. Estimate Your Conversion Rate
Conversion rate typically ranges from:
Weak: 0.5%
Average: 1.0–2.0%
Good: 2.5–4.0%
Strong: 5–10%+
If you’re unsure, use 1–2% as your baseline.
Step 3. Calculate CPA (Cost Per Acquisition)
This determines how much it costs to acquire one customer.
CPA = CPC ÷ Conversion Rate
Example:
CPC = $1.00
CVR = 2% (0.02)
→ CPA = $1 ÷ 0.02 = $50
If your product sells for $40 → Automatically unprofitable.
If your product sells for $120 → Very profitable.
Step 4: Calculate Expected Revenue
This depends on whether you’re forecasting:
First purchase revenue
LTV-based revenue
Subscription revenue
Formula:
Revenue = AOV × Number of conversions
Step 5: Calculate Forecasted ROAS
Use the classic formula:
ROAS = Revenue ÷ Ad Spend
Example:
Revenue = $1,200
Ad spend = $500
→ ROAS = 2.4
Meaning:
Every $1 in ads returns $2.40.
This is the most important forecasting metric for founders.
Forecasting Your Break-Even ROAS
Your break-even ROAS is the minimum threshold at which your ads neither make nor lose money.
Formula:
Break-Even ROAS = 1 ÷ Profit Margin
Examples:
Profit Margin → Break-Even ROAS
20% margin → 5.0
30% margin → 3.33
40% margin → 2.5
50% margin → 2.0
If your forecasted ROAS is below break-even → You lose money.
If it is above → You profit.
Forecasting ROAS Across Different Budget Levels
One of the biggest advantages of ROAS forecasting is modeling different budget scenarios:
Budget → Forecasted ROAS
$100 → ?
$500 → ?
$2,000 → ?
$5,000 → ?
As budgets scale:
CPC increases
CPM increases
Conversion rate changes
Acquisition costs fluctuate
Forecasting reveals the exact point where scaling becomes risky.
Best Practices for Accurate ROAS Forecasting
1. Use conservative numbers
Slightly underestimate conversion rate, slightly overestimate CPC.
2. Use three scenarios
Best case
Likely case
Worst case
Choose a starting budget that works even in the worst-case.
3. Recalculate ROAS every time you update your offer
Even small offer changes have massive impacts.
4. Use a forecasting tool to avoid errors
Manual spreadsheets break easily and are slow.
Real Example: Forecasting ROAS for a $500 Ad Budget
Assume:
CPC: $1.20
Conversion Rate: 3%
AOV: $65
Budget: $500
Forecasted numbers:
Clicks → 416
Purchases → 12.48
Revenue → ~$811
ROAS → 1.62
Profit: ~$311
This allows you to predict your likely outcome before spending anything.
Why ROAS Forecasting Beats Guessing
Most founders guess:
“I think my conversion rate is 4%.”
“I think my ads will work.”
“I think I’ll break even.”
Forecasting replaces “I think…” with:
“I know.”
The Problem With Traditional Analytics Tools
Tools like Triple Whale, Northbeam, and Hyros are incredible for attribution but they:
Do not forecast ROAS
Do not predict profit
Do not model budgets
Do not show future scenarios
Do not estimate expected outcomes
They are backward-looking.
Forecasting is forward-looking.
You need both — but forecasting comes first.
How FounderMode Metrics Simplifies ROAS Forecasting
FounderMode Metrics was built for one purpose:
Predict your ad profits and ROAS before spending money.
It allows founders to:
Model ROAS at different budgets
Predict profit
Estimate CAC
Visualize outcomes
Simulate landing page improvements
Test scenarios instantly
No integrations.
No data setup.
Just forecasting.
Who Should Forecast ROAS Before Running Ads?
ROAS forecasting is essential for:
✔ Startups launching their first ads
✔ Founders planning a monthly budget
✔ Media buyers validating new funnels
✔ DTC brands testing new offers
✔ Coaches, SaaS, ecommerce
✔ Anyone scaling from $100/day to $1,000/day
If you spend money on ads, forecasting reduces risk and increases confidence.
ROAS Forecasting Is a Growth Superpower
ROAS forecasting makes advertising predictable.
It removes guesswork.
It reveals profitability before spending money.
It helps founders scale with confidence.
In 2025, this ability is an unfair advantage.
If you want to stop gambling and start forecasting, tools like FounderMode Metrics enable you to make smarter decisions instantly.