This calculator works backwards from a revenue goal to the ad budget needed to reach it. It uses simple funnel maths: you pay for impressions (CPM), a share of viewers click (CTR), and a share of those clickers buy (conversion rate). Try different inputs to see which lever moves your budget most.
How to use this calculator
- Choose your currency.
- Enter your monthly revenue goal from Meta ads.
- Enter your average order value.
- Enter your CPM, link CTR (%) and conversion rate (%).
- Read the plan: orders, clicks and impressions needed, the monthly and daily ad budget, and the implied CPC, CPA and ROAS.
The formula
Each step feeds the next. Use CTR and conversion rate as decimals (2% = 0.02):
- Orders needed = revenue goal ÷ average order value
- Clicks needed = orders ÷ conversion rate
- Impressions needed = clicks ÷ CTR
- Monthly budget = impressions ÷ 1,000 × CPM
- Daily budget = monthly budget ÷ 30
- Implied CPC = monthly budget ÷ clicks
- Implied CPA = monthly budget ÷ orders
- Implied ROAS = revenue goal ÷ monthly budget
Here CTR means link clicks ÷ impressions, and conversion rate means purchases ÷ link clicks.
Worked example
In rupees (illustrative inputs). Goal ₹6,00,000 a month, order value ₹1,200, CPM ₹150, link CTR 1.25%, conversion rate 2.5%.
- Orders: 6,00,000 ÷ 1,200 = 500
- Clicks: 500 ÷ 0.025 = 20,000
- Impressions: 20,000 ÷ 0.0125 = 16,00,000 (16 lakh)
- Monthly budget: 1,600 × ₹150 = ₹2,40,000, about ₹8,000 a day
- Implied CPC ₹12, CPA ₹480, ROAS 2.5×
In dollars (illustrative inputs). Goal $30,000, order value $60, CPM $12, link CTR 1%, conversion rate 2.5%. That's 500 orders, 20,000 clicks and 2,000,000 impressions: a $24,000 monthly budget ($800 a day), with a $1.20 CPC, a $48 CPA and a 1.25× ROAS.
If your break-even ROAS is 2×, the rupee plan clears it and the dollar plan doesn't. The dollar plan loses money at any budget, so spending more won't fix it. Improve the inputs first, or lower the goal.
How to get your inputs
- CPM and CTR: in Ads Manager, add the CPM (cost per 1,000 impressions) and CTR (link click-through rate) columns for a recent period with meaningful spend. Or work them out from raw spend, impressions and clicks with the CPM calculator.
- Conversion rate: purchases ÷ link clicks for the same period.
- Average order value: from your store's reports rather than your list price, because it reflects bundles and discounts.
New to Meta ads? Run a small test first, then come back with real numbers. For what drives costs in India, read how much Meta ads cost in India.
Why the first month is a learning budget
Your first month buys data as much as sales. New ad sets go through Meta's learning phase, when delivery and costs are less stable, and your first creatives are educated guesses. Don't be surprised if the first month's CPA is higher than the plan.
Size the test budget in purchases rather than money. At a planned CPA of ₹480, ₹24,000 buys about 50 purchases at plan rates, and possibly fewer while you learn. After a few weeks, replace the placeholders with your actual CPM, CTR and conversion rate, re-run the plan, and track real cost per purchase with the CPA calculator.
How to improve a plan that falls short
If the implied ROAS sits below your break-even ROAS (work it out with the break-even ROAS calculator), change the inputs, not the budget:
- Stronger hooks lift CTR, which lowers CPC.
- A faster, clearer product page lifts conversion rate.
- Bundles and add-ons lift average order value, so each order is worth more.
- Broader audiences and more placements can lower CPM.
Once the numbers work, Fly ROAS Autopilot spends inside a monthly cap and a daily limit that only you can raise, so the plan stays a plan.
Frequently asked questions
How much should I spend on Meta ads per month?
Work backwards from your goal: revenue goal ÷ average order value gives the orders you need, and orders × your cost per purchase gives the budget. For example, 500 orders at a ₹480 CPA needs about ₹2,40,000 a month. Check the implied ROAS against your break-even ROAS before you commit.
How do I calculate a daily budget for Facebook ads?
Divide your monthly budget by the number of days you'll run ads, usually about 30. A ₹2,40,000 monthly plan is about ₹8,000 a day, and a $24,000 plan is about $800 a day. Meta can spend more on some days and less on others, so judge pacing over a week rather than day by day.
What CPM, CTR and conversion rate should I use?
Use your own numbers from Ads Manager for a recent period with meaningful spend, not industry averages, because they vary widely by country, category, season and offer. If you haven't advertised yet, run a small test first. Then replace the calculator's placeholder values with what you actually got.
What is a good starting budget for Meta ads?
Size it in purchases rather than rupees or dollars. Multiply your expected cost per purchase by the number of sales you need to judge a few creatives, and treat the first month as a learning budget. At a planned ₹480 CPA, ₹24,000 buys about 50 purchases at plan rates, possibly fewer while you learn.
Why does Meta spend more than my daily budget on some days?
Meta paces delivery across the week, so it may spend more than your daily budget on days with better opportunities and less on others. Weekly spend stays within a limit tied to your daily budget. Meta's Business Help Center explains the current rule. Plan around monthly totals rather than identical daily spend.
