man explaining postback url to people

Everything You Wanted to Know About Postbacks but Were Too Afraid to Ask

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There are very few topics that raise more questions from affiliate marketers than postbacks. For most marketers, an affiliate postback is one of the most common causes of technical headaches. Usually, most affiliates know what a campaign URL is, where a landing page fits in the whole funnel, and have a vague idea of how tracking works. But postbacks? No thank you, sir. I can live without them.

But can you really?

The following article explains what postbacks are, and puts them into the context of advertising. You will learn what they are and why you should use them in your affiliate marketing campaigns.

What Is Postback URL – Postbacks In Short

For a brief moment, stop thinking about affiliate marketing and jump to chats. It is useful to know if someone has got your message and seen it, right? Many chats can generate a response in the background and send you a read receipt to let you know they have.

This is what postbacks in affiliate marketing essentially are — a response. 

In affiliate marketing, the response is triggered when a visitor performs a conversion. It is usually aimed at a tracker that originally redirected a visitor to an offer page.

That was the ultimate “too long, didn’t read” version of the explanation. But don’t worry, the more detailed version is coming.

Affiliate Marketing Campaign Data Flow

Before we will talk more about postbacks, we need to look at the bigger picture. Generally speaking, affiliate marketing is all about managing data that is generated by visitors during their journey from an ad to an offer page. In a typical campaign funnel, there are four parts of the flow:

  1. A visitor is redirected (through tracking software, if used) to a landing page after clicking on an ad. The URL used is called a campaign URL.
  2. A visitor is redirected (again, through tracking software) to an offer page on affiliate’s network side after clicking a CTA button on a landing page. The URL used is called a click URL.
  3. An affiliate network activates a postback URL after a visitor performs a conversion action and the postback URL sends relevant information to the tracking software.
  4. The tracking software automatically activates a traffic source postback URL to report this conversion to a traffic source platform.

As you can see from above, there are actually two postbacks that can be used with a tracker involved: 

  • A postback URL reports conversions to a tracking platform, 
  • A traffic source postback URL reports them to a traffic source platform.

If you do not use a tracker in your campaign funnel, you simply use a traffic source postback URL as the postback URL in your affiliate network platform. But using a tracker is a typical practice for affiliates, so I will continue this article with a tracker included.

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Any of the above-mentioned postbacks, especially the second one, are optional. The campaign funnel will work without them. However, as we have said before, information is key. The more you have it, the more complete picture you will see. Hence, we recommend using both postbacks whenever possible.

Obviously, the flow above can be much more complex, and may include several landing pages and rotating offers. Or it can be simpler, without any landing page. I have shown you here the classic affiliate scenario to demonstrate the logic behind postbacks. But they apply to other scenarios as well.

Tracking Conversions With Postbacks

Postbacks, in general, are URLs that are used to pass information about conversion. They are sometimes also called callbacks, server-to-server (S2S) or cookie-less conversion tracking. They are one of two methods of reporting conversions, the other being the conversion pixel. 

Postbacks allow servers to communicate with each other directly. A client is not involved, no cookies are used on a visitor’s computer. Once activated by a source platform (an affiliate network or tracker), these links send information to the target platform (a tracker or traffic source) in a blink of an eye.

Postback vs Conversion Pixel

Contrary to postbacks, a conversion pixel is a piece of code that has to be implemented on an offer page to report conversions. When this page loads, the script makes a request to a target platform. The script runs on a client’s side. This implicates several differences:

  • Most affiliate networks use postback instead of pixels to report conversions.
  • Most traffic sources support receiving conversions via postbacks. The big exceptions are Internet giants, such as Facebook and Google, which support reporting conversions via their own pixel.
  • Most trackers allow you to receive and pass conversions using both methods, but mixing these methods in one campaign funnel (for example, postback from an affiliate network and pixel to a traffic source platform) may not work.
  • Pixels may not be 100% reliable because they may be blocked or removed by software or user action

Taking all things into consideration, postbacks are usually the recommended method, and pixel should be used as a backup method only. 

How Does Postback URL Work – The anatomy of a postback URL

This is the example of a postback URL:{s2}&payout={payout}

Where: – is your tracking domain, either of your cloud-based or self-hosted tracker.

“? character separates the main part of the link from the tracking parameters.

“& character separates tracking parameters from each other.

cid, payout are tracking parameters that pass values. They are specific for the target platform (a tracker in this case).

{s2}, {payout} are tokens that will be replaced with values when the link is activated. They are specific for the source platform (affiliate network in this case).

Once a visitor converts, an affiliate network platform activates this URL, and tokens are replaced with concrete information. Here’s an example of an activated postback URL:

Available Tracking Tokens

Zeropark offers the following tokens:



{creative­_number} Sends a number of a given creative.
{visit_cost} Sends a visit cost.
{push_type} Tells if it’s push or in-page push traffic type.
{target} Sends a target ID; it is a much more granular traffic placement, it’s actually a source sub-placement.
{source} Sends a source ID; it is a large traffic placement consisting of multiple targets in it.
{keyword} Sends information about keywords attached to the visitor.
{match} Sends a keyword that matched the visit; works only for keyword campaigns.
{cid} Sends a click ID for conversion tracking; this token is mandatory in order to keep a healthy track of your visits.
{traffic_type} Sends information about the traffic type (for example pop, domain or push); for more advanced users it allows to test different traffic types.
{geo} Sends a country code; it is the most commonly used for testing an offer in a multi-geo campaign.
{visitor_type} Sends ADULT / NON-ADULT type of visitor.
{campaign_id} Sends a numeric campaign ID; the token might be particularly useful for external tracking.
{long_campaign_id} Sends a UUID campaign ID; this token is needed for API calls.
{campaign_name} Sends a campaign name.
{os} Sends an operating system name.
{device_id} Send a device ID; for in-app campaigns, you are able to collect some device ID to target afterwards, these can be used to blacklist/whitelist.
{browser} Sends a browser name for desktop or mobile traffic.
{target_url} Sends a target URL; it is only applicable for POPUP campaigns.

Tracking parameters in postback URLs

To ensure the accuracy of the recorded data, tracking platforms have to identify everything that is going on with a visit. So they generate a unique ID and assign them to each visitor’s click on a campaign URL that is hidden behind an ad.

This means that each click has its own, unique value, called click ID. 

This is important, as click IDs are used to verify conversions. After all, a conversion is the money-generating part, so you have to make sure that all of them are real. Trackers do not just accept any postback sent towards them. They only accept the ones that contain their own click ID value that has been assigned to the original click.

  • In the offer URL, you pass a tracker’s click ID value to an affiliate network platform.
  • In the postback URL, it is passed back as proof that this conversion has been triggered by your visitor.

All platforms assign their own click ID values, traffic source and affiliate network platforms do that as well. They also need to keep track of everything that is going on there. In the case of the traffic source postback URL, it has to contain a traffic source’s click ID value that has been passed on to a tracker in a campaign URL. When the tracker receives a postback URL from an affiliate network platform with its own click ID, it activates a traffic source postback URL and sends back the traffic source’s click ID value.

Any other parameters, such as payout or transaction ID, are optional for conversion tracking.

How to set up affiliate postbacks?

Postback templates are supplied by target platforms. So, a postback URL is supplied by a tracking platform, while the traffic source postback URL is supplied by the traffic source platform. The first one has to be submitted to an affiliate network platform, while the other to a tracking platform.

Remember, both tracking and traffic source platforms only supply you with a template. They do not know what tokens are used by the source platform, so typically, a postback URL template looks like this:

You need to put a correct token, dedicated for passing these values. In the case of a click ID, the token has the same name as a parameter name in an offer name, but it is put in brackets. For example, if your offer URL used the s2={clickid} parameter, in a postback URL you should put cid={s2} or cid=#s2#. Refer to your affiliate network’s documentation to learn what tokens you should use.

To sum up, here are the steps for configuring a postback URL:

  1. Pass a tracker’s click ID to an affiliate network in an offer URL
  2. Get a postback URL template from a tracking platform.
  3. Insert affiliate networks tokens into this postback.
  4. Submit the postback URL to an affiliate network platform.

In case of a traffic source postback URL, the steps are similar:

  1. Pass a traffic source click ID to a tracker in a campaign URL.
  2. Get a traffic source postback URL template from a traffic source platform
  3. Insert a tracker’s token that stores a traffic source’s click ID into this postback.
  4. Submit the traffic source postback URL to a tracking platform.

All the visits and no conversions make Jack a dull boy

I’ve talked extensively about what affiliate postbacks are and how to set them up. During this, I’ve mentioned several times that they are used to report conversions, but you still may be wondering: Why should I care about tracking conversions? Why go through all the hassle?

Balancing every budget is about costs and payouts. Cost information is counted by a tracker when a visitor activates a campaign URL. To get information about the payout, you need postbacks. Postback URLs close the loop. With them, you can get the following:

  • Revenue
  • ROI
  • Conversion rate

They allow you to answer the most important questions: Am I making money? And how am I making it?

Traffic source postback URLs should be used if you work with the CPA cost model. To calculate it correctly, you need to let a traffic source platform know how many actions visitors performed. Additionally, some traffic source platforms have AI-based mechanisms that improve your bidding strategy based on your success rate. They also require having conversion information to run.

Are You an Affiliate Postback Pro?

Explaining postbacks is explaining affiliate marketing. That’s why I had to include loads of information in this article.

Don’t worry if you didn’t get everything. Many platforms are already integrated with each other to some degree. This allows for an easier, step-by-step configuration. 

Also, remember that you can always ask your account managers or support for help. They are there for you.

Lastly, I’ve prepared this short quiz with questions about postbacks. You can use it to test what you have learned: