Real-time Bidding API – Frequently Asked Questions

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Getting Started

What is a real-time bidding API?

It’s a way to setup & run display advertising campaigns via a programmatic interface. Increasingly, display media (eg online ads, Facebook ads) are bought and sold in real-time, programmatically. It’s similar to how stocks and currencies are traded on stock exchanges.

How is this different from other “RTB APIs”?

The Merchenta real-time bidding API has been designed to focus on campaign strategies, rather than bid request/bid response processing.

Typically, RTB APIs work at a low level – as a developer you need to accept incoming bid requests, decision on them and provide a valid bid response. Merchenta’s API works at a higher level of abstraction – simply configure your campaign strategy, upload the ad creative and Merchenta will run the campaign for you automatically.

So instead of having to code bidding algorithms, bid handling logic, ad serving logic & provide high-frequency trading infrastructure, Merchanta handles all of this for you – in milliseconds, millions of times a second.

What can I use the Merchenta RTB API for?

Because we take care of the heavy-lifting (eg infrastructure, ad serving, bidding algorithms, content delivery, integrating third party data, sourcing ad inventory), you can build applications which add real value to your clients and your own business.

Typical uses include :

  • Reporting dashboard : use our API to integrate campaign reporting into an existing application or dashboard
  • Campaign management : create a vertical-specific or tailored dashboard to enable users to setup & adjust campaigns
  • DSP-lite : build a demand-side platform quickly and easily

Is this the right solution for me?

We’ve worked hard to make our API simple and easy to use. To make use of the Merchenta RTB API you will need technical software engineering skills to integrate your application into Merchenta.

I work for an ad agency or ad network – is this for me?

Many agencies use the API in conjunction with our white labelled demand side platform, a ready-built DSP-in-a-box solution which is quick to setup, fully rebrandable and which doesn’t require any software development.

Merchenta RTB API is used by organisations of all shapes and sizes from large agency groups through to ad networks through to niche performance marketing agencies. We have clients in EMEA, APAC & North America using our real-time bidding API. We also use the API ourselves for our own managed campaign services.

I just want to drive more online sales for my business!

Merchenta offers a range of risk-free, managed campaign solutions that drive additional online sales for clients on a cost-per-sale (CPA) basis. These solutions include CPA retargeting, mobile/tablet compatible HTML5 dynamically personalised IntelliAds, dynamic product recommendation ads, Facebook retargeting and display prospecting and pre-targeting campaigns.

If you’re unsure what option is the best one for you, just contact us and one of the team will be in touch to help.

Ad Creative

What ad sizes are supported?

Merchenta RTB API supports a wide range of ad sizes and formats, including Facebook Sidebar and IAB standard display units. A full list is available here.

What creative file types are supported?

We support both image ads (eg JPEG, PNG, GIF) and Flash/SWF ads. More details on file formats/sizes is available here.

Do you support 3rd party ad tags?

Yes. All ads run through the Merchenta API must undergo creative review. This is to ensure that all ads run through our platform are editorially and technically appropriate to run with our inventory partners.

What Facebook ad formats are supported?

Presently, we support Facebook Sidebar ads – these are the ads which appear in the right hand side of Facebook pages. We expect to offer news feed ads soon, too.

Why do you review ad creative for all campaigns?

Immediately prior to launching a campaign via the RTB API, our Creative Review team will check the ad creative to ensure it complies with our editorial and technical standards. It’s important to ensure that the ads run via our platform are acceptable to our publisher/website partners. We will also highlight any issues with the prospective performance of your ads (eg direct response ads with no call to action, overly large ad file sizes which will affect load rates etc). For more details check out our creative standards.

How long does creative review take?

We review ads in the order in which they are submitted during European business hours 8am CET to 6pm CET. The process can take 1 to 2 working days, but is often completed same-day. If you have a specific campaign timetable to work to, it’s work factoring in the review process to ensure your campaigns launch when you need them to.

What happens if my ads fail creative review?

A member of our team will contact you via email to explain the problem and suggest ways of rectifying any issues.

Infrastructure & Content Delivery

What is a content delivery network (CDN)?

Merchenta provides a globally-replicated content delivery network (CDN) to ensure speedy ad serving to consumers, wherever in the world they may be. All ads running across the Merchenta platform are automatically deployed to the content delivery network. When an ad is served, it’s assets are pulled off the CDN node geographically closest to the consumer. This means the consumer sees the ad quickly on the web page they are browsing.

Where are the CDN nodes located?

We have CDN nodes all over the world.

EMEA : Istanbul, Copenhagen, Amsterdam, Geneva, Lisbon, Brussels, London, Madrid, Frankfurt, Milan, Stockholm, Budapest, Tallinn, Kiev, Warsaw, Prague, Moscow, Sofia, Bucharest APAC : Singapore, New Delhi, Bangkok ,Hong Kong, Tokyo, Sydney Americas : Phoenix, Denver, New York, Chicago, Seattle,Los Angeles, Portland, Dallas, Montréal, Miami, Atlanta, Toronto, San Paolo

This is a partial list which is growing all the time – if you have a specific region in mind that’s not listed, please contact us.

Where are Merchenta’s bidders/ad servers located?

We operate a global network of our own proprietary bidders, across EMEA, APAC and the Americas. Combined with our content delivery network, our bidders deliver top RTB performance.

We built our own technology because it’s the best way of driving campaign performance for our clients. We do not subcontract or outsource campaigns to third parties.


What geo-targeting options do you support?

We offer a wide-range of geo-targeting options including :

  • Country targeting : run campaigns with specific countries
  • City/town targeting : engage consumers within specific towns and cities
  • Zipcode targeting (USA only) : run campaigns focussed on consumers within specific zipcodes
  • DMA targeting (USA only) : run campaigns focussed on consumers within specific DMA regions

Can I do radius targeting?

Radius targeting can be useful in engaging consumers within a geographical area and the area (“radius”) surrounding that area. Simply setup a radius-targeted campaign and Merchenta will find consumers in that area. This is particularly handy for running campaigns around known locations, for example car dealerships or for new store openings.

  • latitude/longitude : specify a location and a radius in miles
  • town/city : choose one or more towns/cities and specify a radius around it to focus on


What is pre-targeting?

Merchenta RTB API supports a range of pre-targeting strategies, including publisher/site targeting. For example, “run ads on Wall Street Journal website plus”.

Can I get a list of available sites?

The list of available sites is huge. We have access to billions of ads daily across millions of websites. These include well-known “premium” sites, such as,,, – as well as less well-known but often just as effective niche or special interest sites.

Can I run campaigns on specific exchanges?

Yes. By default, all campaigns will run across all available ad inventory to maximise reach. (Note : inventory availability will vary by exchange and also the creative format being used in any given campaign. For example, trying to run a Facebook sidebar ad [99×72] against Doubleclick Adx will result in no impressions being served – as Adx doesn’t support Facebook ad formats – and vice versa).

However, it’s possible to restrict campaigns to one or more exchanges by specifying the exchanges you do not want to use on a per-campaign basis in an exchange blocklist.

What are the exchange codes to use in blocklists?

We are constantly integrating more exchanges and ad networks to Merchenta. Consequently, the list is growing and subject to change – please contact support for an up-to-date list in your chosen region(s).

Contextual Targeting

What is contextual targeting?

Our real-time bidding API supports a range of contextual strategies allowing ads to be run on publisher sites by theme or context. For example, “run ads on websites focussed on Food & Drink, specifically Vegan cuisine”.

Can I get a list of contextual categories?

Sure. Just contact Support with your account details and we will send you the list.

Device Targeting

What is device targeting?

Device targeting is where an ad campaign is directed at a specific device or group of devices (eg desktop computers). It’s important to do this when using particular ad formats which might not run universally on al devices. For example, Flash/SWF-based ads will not run on Apple iPads.

What device targeting options are there?

Merchenta groups devices into 3 taxonomies – desktop (ie PC computers, including Macs), tablet (eg iPads, Galaxy Slate) and mobile (ie something you can make a phone call with). Campaigns can target one or many of these groups.

Third-Party Data Targeting

What is audience/interest-based targeting?

Merchenta provides access to a range of third-party data sources covering a broad spectrum of consumer types and interests. These third-party segments can be combined with campaigns to target consumers with specific interests (eg “looking for a personal loan”).

How can I access third-party data?

Third-party segments can be combined with any campaign created via the Merchenta RTB API. There are a lots of options and data providers available, so we recommend that you contact us to discuss your requirements.

Placement Targeting

What is placement targeting?

It’s the ability to select the locations on a publisher web page to run ads and/or whether that placement is known ahead of time.

What do above/below the fold mean?

Above-the-fold (ATF) is where an ad slot on a publisher page is above the midmark of the screen (ie the “fold”). ATF placements don’t require consumers to scroll their browsers to see the ad, so often are more visible and sell for a premium. Below-the-fold (BTF) is the opposite – ad placements that are below the midmark and which a consumer must scroll to see. There’s also a third category – Unknown – which means either the placement is uncategorised by the publisher or it straddles or spans the midmark and so is both ATF and BTF. It’s possible to select one or all placements types for each campaign via the Merchenta API.

What do “blind” and “transparent” mean?

These terms relate to whether the publisher has permitted Merchenta to know the location of the ads – ie which website or page the ad slot is on. Transparent means that the publisher allows us to see the site domain and – often, but not always – the specific page within that site where the ad slot is located. Blind means that the publisher does not permit the site domain or page to be known. Confusingly, Doubleclick Adx has a third category known as semi-transparent which indicates roughly the site name, but not the page where the ad slot is located. (It would perhaps be better named “semi-blind” for this reason).


What trading currencies are supported?

Unlike most demand side platforms, Merchenta supports a wide range of currencies including US Dollar, Euro, Pounds Sterling and over 30 other currencies. Each RTB API account is associated with a base currency (for example, in Vietnam this might be VND – Vietnamese Dong) which is used for all media transactions and reporting.

It’s also possible to run individual campaigns in a different currency (eg where base currency is Euro, campaigns can be run in a mixture of Euro & US Dollar) – Merchenta will automatically handle the foreign exchange conversion.

What deposit currencies are supported?

By default, RTB API accounts are run on a pre-payment basis. Funds may be deposited by wire transfer in any of the following currencies : USD, GBP, EUR, PLN, SGD, AUD. If you wish to deposit funds in a different currency, please contact us and we’ll be happy to help.

How do I track spend?

The API provides reporting capabilities which enable spend to be tracked both intra-day and inter-day.

Can I run campaigns with my own agency margin?

Yes. For digital agencies & ad networks, we offer the facility to automatically include your margin within media spend for budgeting, reporting and onward billing purposes.

What commercial models do you offer – CPM, CPC, CPA?

The RTB API supports a wide range of bidding algorithms. All API users have access to CPM (cost-per-mille/thousand) algorithms. We also offer CPC (cost-per-click) algorithms via the API for selected partners. For CPA (cost per action/sale) algorithms, please enquire about our managed campaign services.

How much do the ads cost?

We provide a range of bidding algorithms to secure the best ad inventory at the best possible price. Each ad is priced individually with reference to a base price known as the CPM (cost-per-mille or thousand).

The actual price of each ad is decided through a competitive auction process, where each campaign competes with those of other parties (outside Merchenta) for the same ad. The auction process works on a modified Vickrey auction, where the winning bidder pays the price that the second highest bidder offered plus 1 cent. This ensures a fair auction where all participants with access to the auction get an equal opportunity to bid – and if they win the auction the cost will be no more than their bidding price.

Here’s an example – 3 bidders A,B,C

Bidder A – values the ad at $10/cpm
Bidder B – values the ad at $1/cpm
Bidder C – values the ad at $2/cpm

The winner of the auction would be bidder A (as theirs was the highest bid), but the price they pay is just $2.01/cpm (ie bidder B’s bid plus a cent). In practice, the actual cost of that single ad would be less than a cent – $0.00201 (ie $2.01/1000).

What’s a typical CPM for country X?

It’s hard to be prescriptive – media costs can vary significantly by country, placement, ad format, season, time of day, audience etc. Our bidding strategies ensure that media is bought at the best possible price for each campaign.

If you would like an indication of costs for a specific region, contact us.

Brand Safety

What is “brand safety”?

By default, Merchenta automatically verifies the websites and publishers who provide ad placements to ensure that they are appropriate for our advertisers. Any website (or page) which is assessed and found not to be appropriate is blocked and campaigns may not place ads in those locations. A typical example might be “warez” websites hosting “bootleg” downloads or media. We do not permit campaigns to run on these types of sites. For further details on the types of site/content which we restrict, contact your Account Manager.

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