Bid

Written by Cobus van der Westhuizen, reviewed by Wynand van der Westhuizen, fact-checked by Lenata Oosthuizen. Last reviewed July 2026. Editorial policy.

What Is a Bid?

In digital advertising, a bid represents the maximum price you are prepared to pay for a defined action. In Google Ads search campaigns, the most common bid type is the maximum cost per click (CPC), the ceiling you set on what you will pay each time a user clicks your ad. However, bids can also be expressed as cost per thousand impressions (CPM) in display advertising, cost per view (CPV) in video advertising, or as target cost per acquisition (CPA) in automated bidding systems where you specify the conversion value you want to achieve rather than a per-click ceiling.

Bids play a central role in the ad auction. When a user's search query matches your keywords, Google considers your bid alongside your Quality Score to calculate your Ad Rank. A higher bid increases your Ad Rank, but it is not the only lever. An advertiser who has invested in improving Quality Score can achieve a high Ad Rank with a lower bid, reducing cost while maintaining competitive positioning.

It is important to understand the distinction between your maximum bid and what you actually pay. Google's auction is a second-price system: you pay the minimum required to beat the Ad Rank of the advertiser directly below you, not your full maximum bid. This means you will often pay less per click than the ceiling you set. South African businesses running Google Ads in rands can use the Search Terms report and Google's auction insights tool to benchmark their bids against competitive activity and adjust accordingly.

Bid modifiers add another layer of precision. These percentage adjustments allow you to raise or lower your base bid for specific conditions, such as mobile devices, certain times of day, geographic locations, or audience lists. For instance, a Cape Town restaurant might set a +30% bid modifier for mobile users searching within 5 kilometres of the restaurant during lunch hours, increasing the likelihood of showing in the top position for the most valuable audience at the most valuable time.

Bid In Practice

The scenario below is an illustrative example, not a Juicy Designs client result. The figures indicate the scale of effect that careful bid setting typically produces, so treat them as indicative rather than measured.

Imagine a Gauteng-based legal firm setting up a Google Ads campaign for the keyword "family law attorney Johannesburg" and needing to determine a sensible bid. Suppose Google Keyword Planner shows an estimated top-of-page CPC of between R45 and R80 for this keyword, and the firm's intake data suggests that roughly 8% of website enquiries convert to paying clients, each generating an average of around R15,000 in fees. Working backwards, the break-even cost per click would come out at approximately R60. The firm could then set an initial manual CPC bid of R50 and monitor performance over four weeks, adjusting based on actual conversion data as it comes in.

For businesses new to Google Ads, setting bids correctly from the start can be daunting. Starting with manual bidding at a conservative level, then moving to automated bid strategies like Target CPA once sufficient conversion data has accumulated, is a practical approach. Without at least 30 to 50 conversions per month, automated strategies have insufficient data to optimise effectively and may perform worse than a well-monitored manual bid structure.

How bidding works in advertising

A bid is the amount an advertiser is willing to pay for an outcome, a click, a thousand impressions, or a conversion, in an ad auction. In platforms like Google Ads, when an eligible search or impression occurs, an auction runs, and your bid is weighed against competitors' bids and, importantly, the quality and relevance of your ad. Because quality counts, the highest bid does not automatically win; a relevant advertiser can secure a better position at a lower bid. You typically pay only what is needed to hold your position, usually less than your maximum bid. Understanding this explains why relevance is rewarded and why raising a bid widens the auctions you can win rather than simply raising costs proportionally.

Manual versus automated bids

You can set bids manually or let the platform set them automatically. Manual bidding gives direct control over what you pay at the keyword or ad-group level, which suits small accounts, tight budgets, or campaigns with too little data for automation. Automated bidding lets the platform set a bid for each individual auction using signals, device, location, time, audience, that a person could not weigh in real time, optimising towards a goal such as conversions. The trade-off is control for scale and responsiveness. Whichever you use, the bid works within your budget, which caps total spend; the bid influences each auction, while the budget limits how many auctions you enter. Most well-tracked campaigns eventually favour automated bidding for its per-auction precision.

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