How it works
On 9 October 2026 we read Google's help pages on real-time bidding and on Display & Video 360. Google says RTB is the process in which digital advertising inventory is bought and sold, and that it happens in well under a second. Inventory here means the ad space a website or app has for sale.
- A person opens a page or app that has ad space.
- The seller offers that one view to buyers, with details such as the page and targeting information.
- Each buyer's software checks the view and sends a bid with a price per thousand views.
- The winning ad loads on the page.
Google's page on its Authorized Buyers programme says the buyer's system gets targeting details. It then submits a bid that includes a CPM (cost per thousand views).
Who does what
- Publisher: the website or app that has the ad space.
- Ad exchange: the market where that space is put up for sale.
- DSP (demand-side platform): the software an advertiser uses to bid. Google's tool of this kind is Display & Video 360.
- Advertiser: the business that wants its ad seen.
Google's Display & Video 360 help page says it lets you bid and buy inventory from publishers through multiple ad exchanges.
Buying routes
Not every programmatic deal is an open auction. Google's Display & Video 360 pages describe these.
- Open auction: the inventory of an exchange as a whole. If you set no source, Display & Video 360 targets open auction on all enabled exchanges by default.
- Non-guaranteed auction: one publisher invites chosen buyers to bid. The highest bid above the minimum price wins.
A made-up example in rupees
Say a school in Nagpur wants to reach parents who read education news. This is a made-up example. It sets ₹60,000 for a month of display ads on news sites and apps. A cap limits how often one person sees an ad.
- The ads get 1,20,000 views at a cost of ₹500 for every thousand views. That is ₹60,000.
- 400 people click, and 24 fill the enquiry form.
- Cost of each enquiry: ₹60,000 ÷ 24 = ₹2,500.
The school then checks which sites brought enquiries and drops the rest. Views alone do not tell you if the money worked.
Common mistakes
- Starting with a small budget and wanting quick enquiries. Search ads often suit that better.
- Buying on everything open and never checking which sites brought results.
- No cap on how often one person sees the ad.
- Judging success on views and clicks, not on enquiries.
- Ads showing on pages that do not suit your brand. Ask for placement reports.
Programmatic usually comes after Google and Meta ads are working. To see how it fits, read our programmatic advertising page.
Related terms
- Media buying: negotiating and buying ad space on behalf of a brand.
- Retargeting: ads for people who already visited your site.
- CPM (cost per thousand views): the price you pay for every thousand views of an ad.
Sources
- Google Authorized Buyers Help, "Introduction to real-time bidding (RTB)" (support.google.com/authorizedbuyers/answer/6136272), read 9 October 2026.
- Display & Video 360 Help, "Exchanges" (support.google.com/displayvideo/answer/9230278), read 9 October 2026.
- Display & Video 360 Help, "Inventory sources: open auction" (support.google.com/displayvideo/answer/2726009), read 9 October 2026.
- Display & Video 360 Help, "Non-guaranteed auctions" (support.google.com/displayvideo/answer/3289702), read 9 October 2026.

























