PPC Budget Calculator
Work out what your paid search budget actually needs to be. Start from the revenue, customers or leads you want each month, and this calculates the spend required, what it buys at every stage of the funnel, and whether the unit economics support it before you commit a dollar.
Your Numbers
Advanced: fees, repeat purchases, impressions
How To Calculate A PPC Budget
A PPC budget is calculated by working the conversion funnel backwards from a goal. You start with the number of customers you need, divide by your close rate to get the leads required, divide by your landing page conversion rate to get the clicks required, then multiply by your average cost per click. The result is the monthly ad spend that goal demands.
Leads needed = customers needed / close rate
Clicks needed = leads needed / conversion rate
Monthly budget = clicks needed × average cost per click
Most budget conversations start at the wrong end. Someone picks a number that sounds reasonable, spends it, and then finds out afterwards whether it was enough to matter. Running the funnel backwards tells you the answer before the money moves, and it usually tells you one of two uncomfortable things: that the budget required is larger than expected, or that the unit economics do not support any budget at all.
A Worked Example
A commercial roofing contractor wants $120,000 of new revenue a month from paid search. Their average job is worth $12,000, they close one in four qualified enquiries, their landing page converts 8% of clicks, and their cost per click averages $6.50.
- Customers needed: $120,000 / $12,000 = 10 jobs a month
- Leads needed: 10 / 0.25 = 40 enquiries a month
- Clicks needed: 40 / 0.08 = 500 clicks a month
- Monthly budget: 500 × $6.50 = $3,250
That gives a cost per lead of $81 and a cost per customer of $325. With a 45% gross margin, each job contributes $5,400 of gross profit, so $325 to acquire it is comfortable. The plan works, and it works with room to bid harder for volume.
Change one input and the picture changes completely. If the landing page converts at 2% instead of 8%, the same 40 enquiries need 2,000 clicks, the budget becomes $13,000, and the cost per customer rises to $1,300. Still profitable against $5,400 of gross profit, but now the landing page is costing four times what it should. That is the kind of thing a budget model surfaces and a gut-feel number never does.
Break-Even CPA And Break-Even ROAS
Break-even cost per acquisition is the most you can pay for a customer before the sale stops making money. It equals your average order value multiplied by your gross margin. Break-even ROAS is the return on ad spend at which revenue exactly covers both the cost of goods and the media, and it equals one divided by your gross margin.
Break-even ROAS = 1 / gross margin
Maximum CPC = break-even CPA × close rate × conversion rate
These three numbers are fixed by your pricing and your cost structure. They do not change when you raise or lower the budget, which is what makes them the right thing to plan against. A business running a 25% gross margin needs a 4.0x ROAS to break even. One running 70% needs 1.43x. The same 3.0x ROAS is a disaster for the first and a strong result for the second, which is why comparing your ROAS to an industry benchmark tells you almost nothing useful.
Maximum affordable CPC is the number to take into a bidding conversation. It converts the break-even ceiling into the unit you actually control. If your maximum CPC is $8 and the auction clears at $12, no amount of campaign management fixes that. The fix is upstream: raise conversion rate, raise close rate, raise price, or find cheaper demand.
PPC Planning Benchmarks By Industry
These are the planning defaults the calculator loads. They are conservative starting points for a first pass, not published averages and not a forecast. Cost per click in particular varies enormously by geography, by keyword intent and by how many competitors are bidding on any given day. Replace every one of them with your own account data as soon as you have thirty days of it.
| Industry | Cost per click | Conversion rate | Close rate | Gross margin |
|---|---|---|---|---|
| Home services (HVAC, plumbing, roofing, electrical) | $6.50 | 8% | 25% | 45% |
| Legal | $9.50 | 6% | 12% | 70% |
| Healthcare and medical practices | $3.20 | 7% | 28% | 60% |
| Dental | $4.00 | 8% | 32% | 60% |
| B2B services and SaaS | $4.50 | 4% | 18% | 70% |
| Ecommerce | $1.20 | 2.5% | n/a | 45% |
| Real estate | $2.40 | 4% | 8% | 75% |
| Financial services and insurance | $6.00 | 5% | 12% | 65% |
| Marine, RV and powersports | $2.20 | 4% | 14% | 15% |
| Automotive | $2.60 | 6% | 20% | 18% |
| Industrial and manufacturing | $3.80 | 4% | 22% | 35% |
| Education and training | $3.00 | 6% | 15% | 60% |
| Travel and hospitality | $1.60 | 3.5% | n/a | 30% |
Ecommerce and travel show no close rate because the click converts straight to a purchase. There is no separate sales stage, so the funnel has one conversion step rather than two.
The Minimum Budget That Can Actually Be Managed
A budget can be arithmetically correct and still too small to run. Two separate floors apply, and they bind for different reasons.
The learning floor. Automated bidding needs roughly thirty conversions in a rolling thirty days before its predictions stabilise. Below that the algorithm is working from too little signal, results swing for reasons nobody can explain, and the account cannot fairly be judged on its performance. If your plan produces fewer than thirty conversions a month, either fund it to that level or run manual bidding and accept a slower path to learning.
The delivery floor. Below about ten clicks a day, spend arrives in lumps. One expensive auction consumes a meaningful share of the daily budget, impression share becomes erratic, and week-on-week comparison stops being meaningful. At a $6.50 cost per click that floor is roughly $2,000 a month. At $1.20 it is closer to $370.
Where the goal-driven number falls below either floor, the honest framing is that the extra spend is buying data rather than buying customers. That is often the right call, but it should be a decision rather than a surprise.
Five Ways PPC Budget Plans Go Wrong
- Management fees left out of the maths. A campaign at 4.0x ROAS on media can be losing money once a retainer is paid, and small accounts feel flat fees hardest because they do not scale down. Cost per customer should always be calculated on total investment, not on media alone.
- Site-wide conversion rate used instead of landing page conversion rate. The site average includes organic visitors, returning customers and direct traffic, all of which convert far better than a stranger arriving from an ad. Using it inflates the plan by a factor of two or three.
- Lifetime value used to justify the monthly budget. Lifetime value is real, but it arrives over months or years while the ad invoice arrives in thirty days. Budgeting against lifetime value without the cash flow to fund the gap is how otherwise healthy companies run out of money while growing.
- Launching at full budget on day one. The first month is when the account performs worst and the cost per lead runs highest. Spending the most money during the period you understand least is an expensive way to learn.
- Planning against ROAS instead of margin. ROAS is a revenue ratio and revenue is not profit. Two businesses at identical ROAS can be at opposite ends of viability if their margins differ, which they almost always do.
Frequently Asked Questions
How much should I spend on Google Ads per month?
Spend what your goal requires, subject to a floor. Divide your target number of customers by your close rate to get leads, divide leads by your landing page conversion rate to get clicks, then multiply by your cost per click. That is the budget the goal demands.
Separately, no paid search account below roughly thirty conversions a month can be optimised or judged reliably, so that is the practical floor regardless of what the goal-driven figure says. For most small and mid-sized businesses in the United States, a serious paid search programme starts between $2,000 and $5,000 a month in media, plus management.
What is a good PPC budget for a small business?
There is no universal figure, because the answer is set by your cost per click and your conversion rates rather than by your company size. A dental practice at a $4 cost per click can run a meaningful programme on $1,500 a month. A personal injury firm at a $95 cost per click cannot get out of bed for that.
The useful version of the question is what budget clears both floors: enough to produce about thirty conversions a month, and enough to buy at least ten clicks a day. Whichever is higher is your real minimum.
How do I calculate break-even ROAS?
Break-even ROAS equals one divided by your gross margin. At a 40% gross margin, break-even ROAS is 2.5x. At 70% it is 1.43x. At 20% it is 5.0x.
This is why comparing your ROAS to an industry average is close to meaningless. A 3.0x ROAS is a strong result for a software company and a loss-making one for a retailer, and the difference is entirely in the margin.
What is the difference between cost per lead and cost per acquisition?
Cost per lead is total ad spend divided by the number of enquiries generated. Cost per acquisition is total ad spend divided by the number of those enquiries that became paying customers.
The gap between them is your close rate. At a 20% close rate, a $100 cost per lead is a $500 cost per acquisition. Paid search is judged on cost per acquisition, but optimised on cost per lead, because that is the signal the platform can see.
Should management fees be included in the budget calculation?
Yes. A campaign that breaks even on media and loses money once the retainer is paid is not a viable campaign, and leaving fees out is the most common way a budget plan flatters itself.
Percentage-of-spend fees scale with the account and change the arithmetic proportionally. Flat fees do not scale down, so they hit small budgets hardest: a $1,500 retainer on $3,000 of media adds 50% to every acquisition cost.
Can I use customer lifetime value to justify a bigger PPC budget?
You can, but only if you have the working capital to fund the gap. Lifetime value arrives over months or years while the advertising invoice arrives in thirty days.
This calculator reports lifetime revenue separately for that reason, and never uses it to reduce the budget required to hit a monthly goal. Businesses that budget against lifetime value without modelling the cash flow are the ones that run out of money while their revenue is growing.
How long before a new PPC campaign performs to plan?
Budget for ninety days. The first thirty are spent accumulating conversion data the bidding algorithm has none of, and cost per lead typically runs 30% to 50% above target during that period.
The practical implication is that you should not launch at full budget. Start at roughly half, validate that cost per lead is landing where the model says it should, then scale. Launching at the full number spends the most money during the period the account performs worst.
What conversion rate should I use if I do not have one yet?
Use the industry default in this calculator as a first pass, then treat replacing it as the first job of the campaign. Do not use your site-wide conversion rate from analytics: it includes organic, direct and returning visitors who convert far better than someone arriving cold from an ad, and it will inflate the plan by a factor of two or three.
If you have any historical paid traffic at all, even a few hundred clicks, that number is more useful than any benchmark.
What if the calculator says my plan is not viable?
It means your projected cost per customer is higher than the gross profit that customer generates, so every sale loses money and spending more scales the loss.
There are only four real fixes, and none of them is campaign management: raise the conversion rate, raise the close rate, raise the price or margin, or find cheaper demand through different keywords, channels or geographies. Change one of those inputs in the calculator and you can see which lever moves the outcome furthest.
Does this calculator work for Meta, LinkedIn and Microsoft Ads?
Yes. The arithmetic is channel-agnostic: clicks, conversion rate, close rate and margin behave the same way whatever platform sold the click.
What changes is the inputs. Paid social generally has a lower cost per click and a lower conversion rate than paid search, because the audience has lower intent, and LinkedIn typically has the highest cost per click of any major channel. Run the calculator once per channel with that channel's own numbers rather than blending them into one average.
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This calculator produces estimates from the inputs you provide. It is a planning model, not a forecast, and it does not account for seasonality, competitive shifts, auction dynamics or the quality of the campaigns themselves. Treat the output as the budget conversation to have, not the budget to approve.