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Technology and tracking

Click ID

Also called click identifier, clickref, click reference, transaction ID.

Short answer

A click ID is the unique identifier a tracking system generates for every click on an affiliate link. The ID ties click and conversion together: the conversion carries the click ID, and the system looks up the click and decides which affiliate is credited – and at what rate.

Definition of Click ID.

The click ID is created the moment the click happens. The tracking server creates a row with the ID, timestamp, program and affiliate and sends the user on to the store with the ID as a parameter in the URL. From that point on, the ID is the primary key of attribution: everything that has to be decided later – who, how much, within which window – can be looked up via that single row.

The click ID has to survive the journey from landing to purchase. The store's tracking stores it on arrival – in a first-party cookie, in session storage or on the order itself – and sends it along when the conversion is reported back. The server matches the ID against the click row, checks that the purchase falls within the attribution window and credits the affiliate. Without the ID, the conversion cannot be traced back to a click, and then there is no attribution.

The click ID model separates two things that are often confused: where attribution is decided, and how the ID is transported. The cookie is just one possible means of transport between pages – the decision itself sits in the click row on the server. That makes the model robust against browser restrictions such as ITP: a cookie's lifetime can be cut to 7 days, but the click row and its timestamp are untouched.

From click to credit – the 5 links in the chain

1. The click hits the tracking server, which creates the click row and generates the ID. 2. The user is redirected to the store with the ID in the URL. 3. The store's tracking stores the ID locally. 4. On purchase, the store sends the conversion with the click ID, order ID and order value. 5. The server looks up the click row, validates the window and creates the commission.

Every link can break. URL parameters can be stripped by redirects or consent tools; local storage can be cleared; a checkout on another domain can lose the ID along the way; and conversion calls can be missing the field. So test the whole chain – click, landing, purchase, recording – before a program goes live, and again after any change to the store's checkout.

Click ID vs. cookie

AspectClick IDCookie
What it isa key to the click row in the databasestorage space in the user's browser
Where it liveson the tracking serverin the browser, subject to its rules
Lifetimeset by the system and the windowcan be cut by ITP to 7 days or 24 hours
Role in attributiondecides who is creditedcan carry the ID between pages
Survives clearing browser datayes – the row lives on the serverno

The cookie is a means of transport, the click ID is the proof: attribution is decided by the ID the conversion carries – not by whether a cookie still exists.

How it goes wrong

  • 01

    The parameter is stripped along the way

    Redirect chains, consent tools and URL rewrites can remove the ID parameter before the store's tracking has a chance to store it. Attribution dies silently – the click exists, but the conversion can never be matched. Test the chain end to end.

  • 02

    The ID only lives in a script cookie

    If the click ID is stored only in a cookie set with JavaScript, it is gone after 7 days at most in Safari. Long attribution windows require the window to be decided server-side from the click row – not by whether the cookie survives.

  • 03

    The conversion is sent without the ID

    An integration that sends the order ID and amount but forgets the click ID produces sales nobody is credited for. The symptom is clicks without conversions combined with orders that never show up in tracking.

At Affilyflow

Click ID in practice

Affilyflow has one attribution model: the conversion is credited to the click ID it carries. There are no optional models and no estimates – if the ID can be looked up and the purchase falls within the window, the sale is traced back to that click's affiliate.

The click row is also the lock on the deal. At the moment of the click, the commission rate and type are copied to the row, and the attribution window is locked and decided on our server – not in the browser. The click is recorded via the /go link, the ID travels to the store as the afid parameter, and the conversion reports the ID back. Known bots get no click record and therefore never a click ID.

Frequently asked questions

What is a click ID?

A click ID is the unique key the tracking system generates when an affiliate link is activated. It is stored server-side together with the time, program and affiliate, follows the user to the store as a URL parameter and is sent back with the conversion, so the sale can be traced back to the right click.

What happens if the click ID is missing from the conversion?

Then the sale cannot be attributed to an affiliate. The most common causes are URL parameters stripped by redirects or consent tools, a checkout on another domain, and integration errors where the field is never sent. The fix is to test the whole chain from click to conversion call.

Is a click ID the same as a cookie?

No. The click ID is the key to the click row on the server, where attribution is decided; the cookie is just one way of carrying the ID between pages in the browser. If the cookie is deleted, the click row remains – but the ID still has to arrive with the conversion for the sale to be credited.

How long is a click ID valid?

For as long as the attribution window is open. At Affilyflow, the window is locked at the moment of the click and decided on the server from the click's timestamp – its length is set by each program and ranges from a few days to several months. A purchase after the window has closed is not credited, even if the ID is still carried along.

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