Online Advertising in 2026 Explained: Channels, Costs, and Campaign Setup
This post is also available in:
PT 
ES
Online advertising is the practice of promoting products or services through digital channels such as websites, search engines, social media platforms, and mobile apps.
It has become the dominant marketing channel worldwide, with global digital ad spending expected to exceed $740 billion.
Businesses promote their products through multiple digital formats – including search ads, social media campaigns, and high-impact formats like Popunder ads.
In this guide, we’ll walk you through how online advertising works, explore the main models and channels, and show you the key steps to launching and optimizing a campaign.
What Is Online Advertising and How Does It Work?
Online advertising is a way to promote your products or services online and reach the people who are most likely to be interested in them. Unlike traditional ads, digital advertising lets you choose who sees your message and track how it performs, so you can understand what’s working and what needs improvement.
You can place online ads in two main ways:
- Direct placements. Advertisers negotiate fixed placements with publishers, media platforms, or influencers (for example, sponsored posts or banners on specific websites).
- Programmatic advertising. Ad placements are purchased automatically through technology-driven systems. These systems use audience data and bidding mechanisms to distribute ads dynamically.
Operational Advantages of Digital Advertising
Compared with traditional advertising channels, digital campaigns provide several advantages.
- Granular audience segmentation. Advertisers can define precise audience segments using parameters such as GEO location, device type, operating system, demographics, user interests, and behavioral signals. Programmatic platforms allow advertisers to reach users who are most likely to engage with a specific offer.
Here is an example of how targeting settings appear inside the PropellerAds advertising platform:
PropellerAds targeting settings interface screenshot
PropellerAds targeting settings interface screenshot
- Global inventory access. Online advertising platforms provide access to advertising inventory across millions of websites and applications worldwide. This allows advertisers to run campaigns across multiple countries and scale traffic quickly.
- Dynamic creative optimization. Digital campaigns allow advertisers to test multiple creatives and messaging variations. By monitoring performance metrics such as CTR and conversion rate, advertisers can continuously improve campaign effectiveness.
- Real-time campaign analytics. Online campaigns provide immediate performance feedback. Advertisers can monitor impressions, clicks, conversions, and ROI while the campaign is running and adjust targeting, bids, or creatives accordingly.
Online Advertising Pricing Models and Bidding Explained
Online advertising is built around automated systems that connect advertisers with available ad placements across digital platforms. In most modern environments – especially in programmatic advertising – this process relies on bidding mechanisms and pricing models.
How Bidding Works
A bid is the maximum amount an advertiser is willing to pay for an impression, click, or conversion. When a user visits a webpage or opens an application, advertising platforms evaluate available inventory and initiate an automated auction among advertisers targeting that audience.
In programmatic advertising, this auction typically takes place through a system called Real-Time Bidding (RTB).
Real-Time Bidding (RTB) is an automated auction process where individual ad impressions are bought and sold in real time. When a user loads a webpage, advertisers instantly submit bids for that impression, and the highest eligible bid wins the ad placement within milliseconds.
Importantly, the bid represents the maximum price an advertiser is willing to pay. The final price may be lower depending on auction rules and competition.
Note: In direct placements – for example, when you pay an influencer for a sponsored post – bidding does not apply. Pricing is usually fixed or negotiated in advance. However, the overall campaign planning process remains the same.
Pricing Models and Smart Bidding Strategies
While bidding determines who wins an ad placement, pricing models define how advertisers are charged within that system.
The most common pricing models include:
- CPC (Cost Per Click) – advertisers pay only when users click on their ad.
- CPM (Cost Per Mille) – advertisers pay for every 1,000 impressions – the industry standard unit used to measure large volumes of ad views.
- CPA (Cost Per Action) – advertisers pay only when a specific conversion occurs, such as a purchase or registration.
Beyond these standard models, many modern platforms offer smart bidding strategies. For example, PropellerAds’ CPA Goal allows advertisers to set a target CPA, while the system automatically optimizes bids and traffic to achieve it.
Types of Online Advertising: Channels and Formats
Online advertising can be divided into two key components: channels (where ads appear) and formats (how ads are displayed).
- A channel refers to the platform or environment where advertising is delivered – for example, search engines, social media, websites, or email.
- A format refers to the visual or technical structure of the ad itself – such as banners, videos, native ads, or push notifications.
In practice, advertisers rarely rely on a single traffic source,” says Serge Abramov, a head of media buying at AdTech Holding. There’s always a chance this approach will help you discover new users while also retargeting the existing ones. From my experience, I might run campaigns, say, primarily on popunders, where up to 90% of the traffic comes from that format. Even when popunder performance is already strong, there’s usually still something valuable to find in other sources – even if it’s just additional segments or placements within the same popunder network.
Advertising Channels
In this part, we will explain the most popular channels advertisers use and combine.
Note: Even though it seems pretty clear what each type of advertising is, where it begins and where it ends, it’s not really like that in practice. Especially these days, when they are often being mixed and matched. Like, when you’re watching an Instagram feed ad, and you’re not sure if it is native, social media, video, or mobile.
- Email marketing
An example of PropellerAds email marketing.
Email marketing’s point is to collect subscribers and then, based on their willingness to receive and engage with emails, present them with the most compelling offers.
According to HubSpot’s marketing benchmarks, the average email click-through rate across industries is around 2.3%. You can send emails, but chances are they will often be overlooked. This is why most advertisers don’t use email marketing as a stand-alone advertising strategy, but treat it as just a piece of the whole puzzle.
- Search Engine Marketing (SEM)
An example of how SEM works.
Search engine marketing (SEM) is basically PPC (pay-per-click) advertising, and what it does is place the content you want to promote at the top of the search engine results page. So whenever a random user types in a search field of a browser, the keyword you selected to trigger your ad, your post will show up at the top of the page.
This type of advertising is used when the goal is to increase the number of conversions without relying on SEO, or as an addition to it.
Note: PPC ads are marked as what they are, so quite often users decide not to click on them but to move a bit lower and go with the first organic results. Despite that, SEM might increase your visibility on search engines.
- Native advertising
An example of native ads placed at a content site.
These ads blend with the rest of the content on a web page, and it’s usually hard to establish what is and isn’t an ad when browsing through the site. In most cases, they tend to elaborate on some specific issue and then offer a solution, where you have a chance to present your product or service in a natural and unobtrusive way.
- Social media advertising
An example of a social media ad blended in the social feed interface.
Social media ads appear on the platform’s newsfeed when the user is scrolling through it. According to a PYMNTS study, more than 40% of social media consumers browse these platforms in search of products and services.
- Influencer marketing
An example of an influencer’s post.
Influencer marketing can be very direct, where influencers mention the post is a paid ad, or it can be a bit more subtle, where they will promote the product through a more personal approach and just tag the brand.
- Video advertising
An example of a video ad on YouTube.
There are two ways of advertising via videos. The first one is through paid ads that will be showcased on video platforms like YouTube or TikTok, where there’s a great number of daily users, and the second one is creating your own original video content and sharing it on the same or similar video-sharing platforms like Vimeo in order to reach your targeted audience.
- Display advertising
An example of a display ad on the news website.
These are visual ads placed on a third-party website, and their main goal is to attract new customers who are not familiar with the brand or the offer. They can also serve the purpose of retargeting and attracting users who have already visited your website.
Display advertising involves multiple visual and interactive creatives, and this is where ad formats are most commonly discussed.
Advertising Formats
While channels define where ads appear, formats define how they look and function. Here are the most common formats you can come across:
- Banner Ads. Static or animated visual ads placed on websites or apps.
- Video Ads. Pre-roll, mid-roll, or in-feed videos, distributed across platforms or programmatic environments.
- Native Ads. Sponsored content that matches the surrounding editorial design.
- Push Ads. Notification-style ads, delivered directly to users’ devices. Push ads are commonly distributed through ad networks and performance platforms and are often used for high-visibility engagement campaigns.
- Popunder Ads. Ads that open in a new browser tab or window behind the active page. Popunders are typically used in performance-focused campaigns and are commonly distributed via ad networks.
- Interstitial Ads. Full-screen ads that appear between content transitions, often on mobile devices.
In addition to standard advertising formats, some platforms offer unique ad solutions designed to increase engagement and conversion rates. A couple of examples:
- Survey Exit Ads. An interactive, unique format designed by PropellerAds that targets users right after they complete a survey and thus brings the most engaged and conversion-ready audience.
- Telegram Mini App Ads. Ads that allow advertisers to reach engaged users inside Telegram Mini Apps.
Note: Some networks also offer a Multiformat option that’s perfect for advertisers interested in running Push ads, because this feature will automatically create and launch both Popunder and Interstitial campaigns. So basically, you can combine three campaigns within a single setup.
How to Launch an Online Advertising Campaign
Launching a successful campaign requires a clear strategy and a step-by-step approach. To make the process more practical, we’ll use a programmatic campaign example to walk through each step.
Step 1: Define Your Campaign Objective
It’s very important to be clear on what you want to achieve with your ads. Whether it’s encouraging users to make a purchase, register an account, or subscribe, or you want to focus on simply improving your brand awareness and getting an increase. It will help you move to the next step of targeting your audience and launching an on-point campaign.
Step 2: Identify and Understand Your Target Audience
Ask yourself:
- Who is your ideal customer?
- What are their needs and pain points?
- What motivates them to take action?
In programmatic environments, audience targeting can be configured using parameters such as GEO, device type, operating system, demographics, and interest-based segmentation.
For example, demographic and interest targeting allows advertisers to refine audience groups based on age, gender, and behavioral signals, improving campaign precision and overall efficiency.
Step 3: Create Attention-Driven Ad Creatives
When creating ads, the most crucial thing is to make sure they capture the attention of your audience. Both the text and visual parts of the ad are important and will convey your message. And the message should be clear, leaving no room for doubt on what the ad is about. Also, CTA is a must – it will lead the users to your offer.
Source: Ads of the World
Step 4: Configure Targeting and Optimize Bidding
Once the campaign structure is ready, move to setup and optimization. A simple way to do it is to go step by step:
-
Lock in your targeting (GEO, device, OS) and define the vertical. Start with the basics: choose locations, device types, and operating systems that match your offer. Then clearly define your vertical (for example: iGaming, Dating, Utilities, Finance). This helps you pick the right creatives, audience expectations, and traffic sources from the start.
-
Set up Postback/Tracking before spending serious budget. Make sure postback/tracking is connected so conversions are recorded correctly. Without tracking, you won’t be able to optimize bidding or segment performance based on real outcomes.
-
Apply Frequency Capping to control repetition. Use frequency capping to limit how often the same user sees your ad. This helps avoid audience fatigue, reduces wasted impressions, and keeps CTR and conversion rate from dropping over time.
-
Test segments and monitor Fill Rate. Run a few focused test segments (for example, separate campaigns or ad sets by GEO or device). Watch not only performance metrics, but also fill rate – it shows whether your targeting and bid are allowing the platform to deliver enough traffic. If the fill rate is low, you may need to broaden targeting, increase bids, or adjust campaign settings.
-
Use White/Black Lists to improve quality fast. As data comes in, build whitelists (sources/placements that perform well) and blacklists (sources/placements that waste budget). This is one of the quickest ways to increase efficiency without changing the whole campaign strategy.
-
Optimize bidding using eCPM as a common benchmark. Adjust bids based on performance. Start with a competitive bid to enter auctions and gather data, then increase or decrease it depending on CTR and conversions.
-
Scale what works, cut what doesn’t. Pause underperforming segments, expand budgets on stable winners, and keep iterating: test new audiences, creatives, and whitelist expansions. Continuous optimization is what makes campaigns scalable and profitable.
Step 5: Campaign Optimization Workflow
In performance advertising, launching a campaign is only the beginning. Most profitability comes from systematic optimization based on real performance signals such as CTR, conversion rate, and traffic quality.
A typical optimization workflow includes the following steps.
- Configure tracking and postback. Before scaling budgets, ensure that conversion tracking is correctly configured. Postback URLs allow advertising platforms to receive real-time conversion data and optimize campaigns accordingly.
- Apply frequency capping. Use frequency capping to limit how often the same user sees an ad. This prevents audience fatigue and helps maintain stable CTR and conversion rates.
- Test segments and monitor fill rate. Launch multiple targeting segments and evaluate performance across them. Monitor fill rate, which indicates whether the platform can deliver sufficient traffic for the chosen targeting and bid levels.
- Build white and black lists. As data accumulates, identify high-performing placements and add them to whitelists. Low-performing sources should be excluded using blacklists to prevent wasted spend.
- Monitor traffic quality and fraud detection. Use fraud detection tools to identify invalid traffic, such as bots or suspicious clicks. Filtering low-quality traffic ensures optimization decisions are based on genuine user behavior.
- Optimize bids using eCPM. Adjust bids based on campaign performance. Many advertisers use eCPM (effective cost per mille) as a benchmark to compare traffic sources and targeting segments objectively – we’ll cover this topic in more detail in the next section.
- Scale profitable segments. Once profitable placements or targeting segments are identified, gradually increase budgets and expand campaigns to similar audiences.
Note: Although the mechanics differ between direct placements, search advertising, social media campaigns, and programmatic environments, the strategic logic remains the same.
- In influencer marketing, targeting happens through selecting creators whose audience matches your ideal customer profile.
- In search advertising, targeting is keyword-based and focused on user intent.
- In social media advertising, segmentation relies on platform-level demographic and behavioral data.
- In programmatic campaigns, targeting is configured through automated systems using audience signals and bidding mechanisms.
The tools vary – but defining goals, understanding your audience, allocating budget, launching creatives, and optimizing performance are universal steps.
Online Advertising Cost Benchmarks
The cost of online advertising varies depending on the channel, audience targeting, competition, and geographic location. In many digital advertising environments, costs are often compared using CPM.
| Advertising Format | Min CPM | Avg CPM | Max CPM |
| Display Banner Ads | $0.20 | $1.50 | $6 |
| Native Advertising | $0.50 | $2.50 | $8 |
| Push Notifications | $0.10 | $1.20 | $5 |
| Popunder Ads | $0.30 | $1.80 | $7 |
| Video Ads | $4 | $12 | $30+ |
Actual CPM values can vary depending on GEO, targeting precision, competition in the auction, and overall campaign optimization.
Even when campaigns are priced using CPC or CPA models, advertisers often evaluate performance using eCPM (effective cost per mille). This metric converts different pricing models into the equivalent cost per 1,000 impressions, making it easier to compare campaign efficiency across traffic sources and pricing structures.
For example:
- In a CPC campaign, 1,000 impressions with a 2% CTR generate 20 clicks. If the CPC is $0.20, the total cost is $4, meaning the eCPM equals $4.
- In a CPA campaign, the same 1,000 impressions lead to 2 conversions with a $2 CPA, resulting in $4 total cost and an eCPM of $4.
Even though the pricing models differ, converting both campaigns to eCPM shows that the effective cost per 1,000 impressions is the same.
Pros and Cons of Online Advertising
Online advertising offers strong advantages such as precise targeting, real-time analytics, and automated campaign optimization. These capabilities allow advertisers to scale campaigns quickly and reach global audiences.
However, advertisers must also consider several limitations. Competition can increase traffic costs, optimization algorithms require a learning period, and incorrect tracking setup may affect attribution accuracy. Understanding these factors helps advertisers build more stable and efficient advertising strategies.
✓ Advantages
Reach users by GEO, device, interests, and behavior.
Campaign performance can be tracked and optimized instantly.
Algorithms optimize bidding and delivery based on conversion signals.
Advertisers can scale campaigns across multiple regions.
Budgets can increase quickly once performance stabilizes.
⚠ Limitations
Popular verticals often experience higher advertising costs.
Algorithms require time to gather optimization signals.
Incorrect attribution setup can distort campaign performance data.
Platforms enforce moderation and advertising guidelines.
Performance may vary depending on platform and audience quality.
Final Thoughts
The predictions are that ad spending within digital advertising will reach US$1.25 trillion in 2026.
With that said, it is essential to stay up to date with trends and make sure you are following all the right currents in the online advertising world.
So let’s take another look at all the relevant aspects of online advertising, at this very moment:
- There are more than 5 billion Internet users in the world
- Almost half of social media users worldwide browse these platforms in search of products and services
- Defining your goals and targeting your audience are the two essential steps within any digital advertising campaign
- For high campaign performance, it’s important to combine several types of online advertising and not rely on only one
- Choosing the right ad network and ad format is what can make or break your campaign
In case you need some help navigating these unsteady waters, join PropellerAds now and launch your first campaign!
Join our Telegram for more insights and share your ideas with fellow-affiliates!
Trends
View more posts
