The short answer
To calculate a Meta Ads budget, work backwards from the revenue goal. Sales needed = revenue goal ÷ price. Clicks needed = sales ÷ conversion rate. Cost per click = CPM ÷ (1,000 × CTR). Budget = clicks × cost per click. Example: ₹2,00,000 goal, ₹10,000 price, 2% conversion, ₹150 CPM, 1% CTR gives a ₹15,000 budget.
Before you start
By the end of this SOP
A budget estimate, cost per sale and a clear view of whether the goal is realistic.
- Time
- 15 minutes
- You’ll need
- A revenue goal and price, plus CPM, CTR and conversion rate from past campaigns or the client’s website.
- Who does this
- The person planning paid campaigns or writing the proposal.
About this SOP: why it matters, where and when
Why it matters: Clients ask “How much should I spend?” This gives a reasoned answer, not a guess.
Where: In a Google Sheet, using numbers from Ads Manager and GA4.
When: When planning a campaign, writing a proposal (SOP 038) or setting monthly budgets.
Stage 1
Gather the five inputs
- 1
Write down:
- Revenue goal for the period, e.g. ₹2,00,000 this month.
- Average price or order value, e.g. ₹10,000 per course.
- CPM (cost per 1,000 impressions) from Ads Manager, last 90 days.
- Link CTR (link clicks ÷ impressions) from Ads Manager.
- Website conversion rate (sales ÷ landing-page visits) from GA4 or the store.
Tip
No history yet? Use a conservative guess and say so in the proposal. Replace it with real numbers after the first 2–3 weeks.
Stage 2
Work backwards to the budget
- 1
Sales needed = revenue goal ÷ price. Example: ₹2,00,000 ÷ ₹10,000 = 20 sales.
- 2
Clicks needed = sales ÷ conversion rate. Example: 20 ÷ 2% = 1,000 clicks.
- 3
Cost per click = CPM ÷ (1,000 × CTR). Example: ₹150 ÷ (1,000 × 1%) = ₹15.
- 4
Budget = clicks × cost per click. Example: 1,000 × ₹15 = ₹15,000.
- 5
Cost per sale (CPA) = budget ÷ sales. Example: ₹15,000 ÷ 20 = ₹750 per sale.
Stage 3
Sanity-check it
- 1
Is the cost per sale well below the profit per sale? If not, the goal needs a better offer, price or conversion rate, not more budget.
- 2
Adjust for the real world before you send the number to a client:
- Add 18% GST: Meta charges it on top of ad spend in India. ₹15,000 of ads → about ₹17,700 billed.
- Not every click lands: on Indian mobile networks 30–50% of link clicks never load the page. Use cost per landing page view, not cost per click, if you have it.
- Courses and high-ticket services rarely sell straight from an ad. Model the real path instead: leads → counselling calls → enrolments, with rates from the client’s CRM.
- 3
Change one input at a time to see the risk, e.g. what if conversion rate is 1% instead of 2%? (Budget doubles to ₹30,000.)
Watch out
This is an estimate, not a promise. Real costs change with season, competition and creative. Never guarantee results to a client.
- 4
Add a testing buffer (often 10–20%) for the first month while campaigns learn.
Agency playbook
Doing this for a paying client
What a senior checks before calling the job done. Numbers are starting rules; compare them with the account’s own history.
What good looks like
- The budget lets each ad set buy about 50 results a week at target CPA (cost per sale). If not, use fewer ad sets or an earlier event.
- Breakeven CPA comes from margin, not price. A ₹10,000 course with ₹4,000 margin means the maximum you can pay per sale is ₹4,000.
- The client sees three scenarios, conservative, expected and stretch, each with its assumptions written beside it.
- The monthly budget is broken into weekly pacing targets, so overspend or underspend shows within days, not at month-end.
- Ad spend, 18% GST and agency fee are shown as separate lines, never bundled into one figure.
Mistakes we see on real accounts
- Using a CPM (cost per 1,000 impressions) from a YouTube video or another niche. Real costs come in double and the client feels misled.
- ₹500 a day for a ₹3,000 CPA. The campaign never exits learning and every report says “still unstable”.
- Quoting ₹30,000 without GST. The client sees ₹35,400 charged and trust drops before the first report.
- Splitting a small budget across many audiences or placements. Each piece is too small to learn anything.
Agency checklist before you call it done
- Every input has a source and date: which ad account, which 90 days, which GA4 (Google Analytics 4) report.
- Budget sheet saved in the client folder with version and date.
- The client can fund at least 4 weeks (starting rule) without pausing mid-learning.
- Account spending limit and campaign budgets match the approved number.
- Client approved the budget in writing, including the line “estimate, not a guarantee”.
- Change-log entry for every budget change, with the reason.
- Monthly check: Meta invoice vs planned spend vs what the client actually paid.
Handover message to the client
Hi [Client name], for your goal of ₹[2,00,000] in sales this month, we recommend ₹[15,000] ad spend + 18% GST (₹[17,700]), plus a 15% testing buffer. Expected cost per sale ₹[600–900]. This is an estimate, not a guarantee; we’ll update it after 2 weeks of real data.
Senior tip
Budget on marginal returns, not averages. Each extra ₹10,000 usually buys sales at a higher cost than the last. Track cost per sale at each budget step and stop scaling when the extra sales cost more than breakeven.
Practice & check
Now do it for real
Reading is not doing. Open your own account and complete this task before you move on.
Practice task (5 min)
Calculate the budget for a real or practice business with your own inputs. Then recalculate with conversion rate halved and explain the difference.
Prove it
Two questions. Get both right and this SOP is done.
Common questions
What is a good CPM for Meta Ads in India?
It varies by audience, season and objective. Use the CPM from your own or similar past campaigns rather than a general average.
How much should a small business spend on Meta Ads?
Work backwards from the goal using this formula, then start with an amount you can run for at least a few weeks without stopping.
Done. That’s a real skill, not a certificate.
Want to do this on real client budgets, with a mentor checking your work? That’s Level 2 at Unlearn. See the Digital Marketing track