How do I make my cost per click (CPC) cheaper in Google Ads?

Imagine you pay $1 per click and 1 in 100 clicks becomes an enquiry. That's $100 per enquiry.

Now imagine you pay $10 per click and 1 in 10 becomes an enquiry. That's also $100 per enquiry.

Same result. So the price of a click isn't your real problem. The price combined with the conversion rate (the share of clicks that become enquiries) is. That has a practical consequence. Don't remove a keyword just because it costs more, or favour one because it costs less, until you know which one produces enquiries.

To compare fairly, you need to compare like with like: the same keyword, the same time of day and day of the week, the same device, the same kind of person. Otherwise you may simply be favouring one type of searcher over another, and they may convert very differently.

With everything else equal, here's how to pay less.

Google runs an auction every time someone searches. Your position and your price depend on your Ad Rank, roughly your bid combined with your ad's quality. A higher-quality ad can pay less per click than a lower-quality ad for the same ad position.

Think of it as Google owning 20 flats in a prime location. If your ad is shown again and again and nobody clicks, it's a flat standing empty, and Google earns nothing from it. It would rather give the space to an ad that gets clicks. So ads that get more clicks pay less per click, and ads that get fewer clicks pay more.

Google lists three things it looks at.

1. Expected click-through rate

Click-through rate (CTR) is the percentage of people who see your ad and click it. Google predicts yours before the ad runs, based on how your ads and keywords have performed. Google doesn't publish how much each of the three things counts for, but I think this one matters most, and the other two mostly feed into it.

2. Ad relevance

Google says this is how closely your ad matches what the person searched for. That's why one ad group per kind of ask matters. If someone searches "workplace CPR training" and your ad talks about general first aid, it's less relevant.

My view is that "ad relevance" is also expected CTR in disguise. Google doesn't spell out how it measures relevance, and an ad that repeats the keyword usually gets clicked more, so the two tend to move together. If an ad without the keyword's words got a much higher CTR than one that repeated them word for word, I'd expect the high-CTR ad to win.

3. Landing page experience

This is the page people reach after clicking. Google says it assesses how relevant, useful and easy to use the page is, including how fast it loads and how well it works on a phone.

It's hard to tell from outside how much this moves your CPC, so I wouldn't start here. But fix the obvious problems: a slow page, one that works badly on a phone, or one that doesn't mention what the ad promised.

Do the best you can with the page. But in most accounts, getting more relevant people to click does more than most landing page tweaks.

Google charges less per click to ads that get clicked, so make your ads relevant to the right people. But don't chase a higher CTR for its own sake: a cheap click from the wrong person is the most expensive thing you can buy.