PPC vs CPC: What Is the Difference?

PPC and CPC are not rivals: PPC (pay-per-click) is the advertising model, and CPC (cost-per-click) is the price you pay for each click inside that model. PPC describes how you buy traffic, such as Google Ads search campaigns. CPC is a metric that tells you what each click actually cost. You run PPC campaigns and you measure, bid and budget with CPC.

The two terms get swapped around constantly, in agency proposals, job adverts and even inside Google Ads itself, where “CPC” also names a bidding option. That confusion matters more than it sounds. A business owner who thinks a low CPC means a good PPC campaign can end up paying for cheap clicks that never become enquiries. This guide sets out what each term means, how Google works out the price of a click (based on Google Ads Help as of October 2026), and which numbers ProntX looks at when judging whether a campaign is working.

Key takeaways

• PPC is the model (you pay when someone clicks your ad). CPC is the cost of one of those clicks.
• In Google Ads there are three CPC figures: the maximum CPC you bid, the actual CPC you are charged, and the average CPC across many clicks.
• Your actual CPC is usually below your maximum bid, because Google charges only what is needed to beat the advertiser ranked below you and clear the Ad Rank thresholds.
• Better ad and landing page quality can lower what you pay per click.
• CPC is a cost input, not a result. Judge PPC on cost per enquiry or sale and on return on ad spend.

What is PPC?

PPC is an online advertising model where you pay the platform only when someone clicks your ad, not when the ad is shown. The best-known example in the UK is Google Ads search: you choose the searches you want to appear for, write the ad, set a budget and are charged per click.

When people say “we do PPC” they normally mean the whole activity that sits around that model: keyword research, campaign structure, ad copy, landing pages, bidding, conversion tracking and ongoing optimisation. In other words, PPC is a channel and a discipline. Microsoft Advertising works on the same principle, and some display and shopping formats on Google can also be bought on a per-click basis.

What is CPC?

CPC (cost-per-click) is the amount of money you pay for a single click on your ad. Google puts it simply: cost-per-click bidding means you pay for each click on your ads. Because it is a number, CPC is what you see in reports, what you set bids against and what you use to forecast how much traffic a budget will buy.

So CPC sits inside PPC. Every PPC campaign has a CPC, but CPC on its own tells you nothing about whether the campaign is profitable. A £1.20 click that never converts is more expensive, in any sense that matters, than a £6 click that brings in a booked job.

What is the difference between PPC and CPC?

The difference is that PPC is how you pay and CPC is what you pay. One is a pricing model and a type of campaign; the other is a measurement taken from that campaign. The table below sets the two side by side.

What do max CPC, actual CPC and average CPC mean in Google Ads?

Google Ads uses three separate CPC figures, and most reporting confusion comes from mixing them up. Here is what each one means, using Google’s own definitions.

1. Maximum CPC (max. CPC). Google describes this as the highest amount you are willing to pay for a click on your ad. It is a ceiling you set, either by hand or through a bid strategy.
2. Actual CPC. The final amount you are charged for a click. Google says you will often be charged less than your maximum, sometimes much less.
3. Average CPC (avg. CPC). The total cost of your clicks divided by the number of clicks. If two clicks cost £0.20 and £0.40, the average CPC is £0.30. This is the figure most monthly reports quote.

One caveat: Google notes that actual CPC can go above your max CPC when you use bid adjustments or certain automated bidding tools. If you have handed bidding to Smart Bidding, your maximum is no longer a hard limit on each click unless you set bid limits where the strategy allows them.

How does Google decide what you pay per click?

Google charges you only what is needed to clear the Ad Rank thresholds and beat the Ad Rank of the competitor immediately below you. If nobody eligible sits below you, you pay the reserve price. That is why your actual CPC usually lands below your bid.

Ad Rank is the set of values Google uses to decide whether your ad can show and where. According to Google’s explanation of Ad Rank, it takes into account:

• your bid
• ad and landing page quality at the moment of the auction (expected clickthrough rate, ad relevance and landing page experience)
• Ad Rank thresholds, which are typically higher for ads shown above the search results
• how competitive the auction is
• the context of the search, such as the words used, location, device and time
• the expected impact of assets such as sitelinks and other ad formats

Google’s actual CPC help page also notes that competitors further down the auction can influence your price, and that the thresholds for top positions push actual CPC up there. In plain terms: the same keyword can cost very different amounts depending on position, time of day and who else is bidding that hour.

Does a better Quality Score lower your CPC?

Higher quality ads can often lead to lower CPCs, according to Google, because quality feeds into Ad Rank alongside your bid. A relevant ad pointing to a useful landing page can beat a rival with a higher bid and still pay less.

It helps to be precise about Quality Score itself. Google measures it from 1 to 10 at keyword level, based on expected clickthrough rate, ad relevance and landing page experience. Google is also clear that Quality Score is not an input to the auction; it is a diagnostic summary. The auction uses real-time quality signals, and Quality Score gives you a rough view of how those signals look. Treat a low score as a prompt to fix the ad or page, not as a number to chase for its own sake.

How do you use CPC to plan a PPC budget?

Divide your monthly budget by the average CPC you expect to get an estimate of clicks, then apply a realistic conversion rate to estimate enquiries. Running the sum backwards tells you what you can afford to pay per click.

Here is an illustrative worked example. The figures are made up to show the arithmetic; they are not benchmarks for your sector.

1. Monthly ad budget: £1,500.
2. Expected average CPC: £3.00, which buys roughly 500 clicks.
3. Landing page conversion rate: 5%, which gives about 25 enquiries.
4. Cost per enquiry: £1,500 divided by 25, so £60.
5. If one enquiry in four becomes a customer worth £600 in gross profit, six or seven customers bring in around £3,600 to £4,200 of profit for £1,500 of spend.

Now run it the other way. If you can afford £60 per enquiry and your page converts at 5%, the most you can pay per click and stay on target is £3.00 (£60 multiplied by 0.05). Lift the conversion rate to 8% and the same £60 allows £4.80 per click. That is why improving the landing page often gives you more room in the auction than cutting bids does. Our guide to raising PPC conversion rates covers where those gains usually hide, and our breakdown of what PPC costs in the UK explains how management fees sit on top of ad spend.

Is a low CPC always good?

No. A low CPC is only good if those clicks turn into enquiries or sales at a cost you can afford. Cheap clicks often come from broad or loosely related searches, poor placements or audiences with no intent to buy.

We regularly see accounts where the cheapest keywords have the worst cost per lead. A search like “free” plus your service, or a job-seeker query, can cost a fraction of your core terms and convert at nothing. The reverse is also true: high-intent searches such as an emergency service plus a postcode tend to cost more because every competitor wants them, and they are often still the most profitable clicks in the account.

Which PPC metrics matter more than CPC?

Cost per acquisition (CPA) and return on ad spend (ROAS) matter more than CPC, because they connect spend to business results. CPC is one of the inputs that drives them, alongside conversion rate and order value.

Use this decision framework when reviewing a campaign:

• Is conversion tracking recording real enquiries or sales? If not, stop judging anything and fix tracking first. Every other number depends on it.
• Is CPA within the figure you can afford? If yes, a rising CPC is not automatically a problem.
• Is CPA too high while CPC is stable? Look at search terms, landing page and offer before touching bids.
• Is CPC rising and CPA rising with it? Check impression share, new competitors and quality signals on your main keywords.
• Is CPC falling but leads falling too? You may be winning cheaper, weaker auctions. Review match types and negative keywords.
• Selling online? Track ROAS (revenue divided by ad cost) and margin, not just CPA.

If you move to automated bidding, Google’s Target CPA strategy sets bids to get as many conversions as possible around the cost per acquisition you choose. It needs conversion tracking in place, and Google suggests judging it over a 30-day window with at least 30 conversions. Individual conversions will cost more or less than the target; the aim is the average.

A quick checklist before you report on CPC

• State which CPC you mean: max, actual or average.
• Compare like with like: the same campaign, network and device across the same date range.
• Separate brand searches from non-brand, as brand clicks are usually far cheaper and flatter the average.
• Put CPC next to conversion rate and CPA in every report so nobody reads it alone.
• Note any bid strategy changes in the period, since they can shift CPC overnight.
• Check the search terms report for cheap clicks that never convert.

If you would like a second opinion on an existing account, our PPC audit looks at tracking, search terms, bidding and landing pages together. And if you are deciding between paid and organic channels, our comparison of search engine optimisation against paid search in SEO vs PPC sets out when each makes sense.

How ProntX handles CPC in the campaigns we run

At ProntX we set targets from the cost per enquiry or sale a business can afford, then work backwards to the CPC that allows. Reports show average CPC next to conversions and CPA, with brand and non-brand split, so a cheap month never hides a bad one.

Our pay-per-click management starts from £450 a month, on a rolling monthly contract. Ad spend is paid direct to Google from your own account, so you see every click and every penny of CPC yourself. If you want to know whether your current cost per click is working for you or against you, ask ProntX for a free growth audit and we will walk through the numbers on a short personal video.