What Is Pay Per Click (PPC)?
Pay per click, or PPC, is an online advertising model in which advertisers pay each time someone clicks their ad, rather than when it is shown. It is common in search, social, and display advertising. Auctions that weigh bids and ad quality set costs. PPC delivers controllable traffic quickly, but advertisers pay for clicks whether or not they convert.
How PPC works
Advertisers choose keywords, audiences, or placements, write ads, and set bids for what they are willing to pay per click. When a user searches or browses, the platform runs an auction among eligible ads, considering bids and quality signals such as expected click-through rate, ad relevance, and landing page experience. Winning ads are shown, and the advertiser pays only if the user clicks. The actual price is often below the maximum bid, depending on competitors.
What determines cost per click
Cost per click, or CPC, depends on competition for the keyword or audience, the advertiser's quality signals, targeting choices such as location and device, timing, and the platform. Commercial keywords in competitive industries cost more because many advertisers value those customers highly. Improving ad relevance and landing pages can reduce CPC by raising quality signals.
Key PPC metrics
PPC performance is judged with a small set of related metrics. Each measures a different step from impression to revenue.
Click-through rate (CTR)
Clicks divided by impressions. It indicates how compelling and relevant an ad is.
Cost per click (CPC)
Spend divided by clicks. It shows what traffic costs.
Conversion rate
Conversions divided by clicks. It shows how well the landing page turns visitors into leads or customers.
Cost per acquisition (CPA)
Spend divided by conversions. It shows the cost of each result.
Return on ad spend (ROAS)
Revenue from ads divided by ad spend. It shows whether campaigns earn back their cost.
Where PPC fits
PPC is useful for reaching people actively searching for a solution, testing messages and offers quickly, launching in new markets, and promoting time-sensitive offers. It provides traffic on demand and fine control over targeting and budget. Its main drawbacks are that costs rise with competition, traffic stops when spending stops, and advertisers pay for every click whether or not it converts.
PPC versus pay-per-sale models
In PPC, the advertiser pays for traffic and carries the conversion risk. In affiliate and partner programs, the business pays a commission only when a referral converts, so partners carry most of the risk. Many businesses use both: PPC for controllable demand capture, and partners for trusted recommendations and reach that advertising cannot buy. Comparing channels on CPA and customer value, rather than on CPC versus commission rate, shows which delivers better customers for the money.
Affiliates and PPC
Some affiliates run PPC campaigns themselves, paying for clicks and earning commission on resulting sales. This works when their earnings per click exceed their cost per click. Many programs restrict affiliates from bidding on the brand's own name, because those buyers would likely have found the brand anyway, and paying commission on them inflates costs.
Improving PPC results
Common improvements include tightening keyword and audience targeting, adding negative keywords to exclude irrelevant searches, writing ads that match search intent, sending traffic to focused landing pages, testing offers, and optimising bids toward conversions or revenue rather than clicks. Tracking conversions all the way to revenue lets campaigns optimise for customers rather than cheap clicks.
Where PPC spend leaks
Typical mistakes include bidding on broad terms that attract irrelevant clicks, sending all ads to the home page, measuring success by clicks or CTR alone, ignoring mobile experience, and failing to connect conversions to revenue. Another is comparing PPC with partner channels on CPC alone, which ignores the very different risk each model places on the advertiser.
PPC and attribution
Ad platforms report conversions using their own attribution rules, which often credit the ad for any conversion within a window after a click or view. This can overstate PPC's contribution when buyers also interacted with other channels. Comparing platform-reported conversions with your own revenue data, and occasionally testing incrementality by pausing campaigns in selected regions, gives a more accurate picture.
Search versus social PPC
Search PPC targets people who type a query, so it captures existing demand and intent is usually high. Social and display PPC target people by interests, behaviour, or similarity to existing customers, so they are better at creating awareness and reaching people who are not yet searching. Conversion rates and costs differ between the two, and they should be judged against different expectations rather than a single benchmark shared across every platform and campaign.
Frequently asked questions
- How much does pay per click cost?
- It varies widely by keyword, industry, location, and platform. Competitive commercial terms can be expensive per click, while niche terms may be inexpensive. The more useful question is cost per acquisition: what you pay for each customer after accounting for conversion rate, compared with what that customer is worth.
- What is the difference between PPC and CPC?
- PPC is the advertising model, paying for each click. CPC, cost per click, is the metric that measures how much each click costs. In everyday use the terms are sometimes interchanged, but PPC describes the approach and CPC describes the price.
- Is PPC better than affiliate marketing?
- They do different jobs. PPC provides controllable traffic quickly, with the advertiser carrying conversion risk. Affiliate marketing pays only for results and brings trusted recommendations, but takes time to build. Many businesses use both and compare them on cost per acquisition and customer value.