What yclid is and how it traces a click

In the Yandex Metrica glossary, yclid is the identifier of a click on an ad. Direct assigns it and passes it in the URL. The tag is there to tie a visit to a source. The reports do not show yclid itself. Why the account’s clicks and the counter’s visits diverge is covered in why clicks in Direct do not match visits in Metrica. Below is where the number does land, and what not to expect from a cell in the report.

Who inserts the number

The tags help says Direct places yclid. The shape of a link in the example is https://example.com/?yclid=123. The example illustrates the format. It is not a click from a campaign. In the table of dynamic parameters, {yclid} is the same click identifier. The help points to Metrica: the tag is there to trace the source of the visit, and it is passed as a number.

Beside it, {source_type} distinguishes search (search) and networks (context). {source} passes none on Yandex search and the placement’s domain on networks. On search placements of the Yandex Advertising Network either a domain or none may arrive. {source}=none on search is a stock value, not a sign of an empty placement.

Direct itself adds yclid to ad links. If the address is longer than 4096 bytes, values are passed only for the tags yclid and openstat. Cyrillic in the link is encoded in UTF-8, and the address grows because of that. 4096 bytes is the limit on passing tags in this help, not “the length of click fraud”.

What the report sees

Ad visits are looked at in the “Direct” report group: summary, placements, and expenses. Statistics in these reports are counted only on the clicks that were kept, which click-fraud protection did not filter. The “Direct, summary” report opens at “Reports → Sources → Direct, summary”. The help ties bounces in it to leaving within 15 seconds after one page view. If the counter is not linked to the campaign, the visits fall into the source “Other people’s campaigns”.

Metrica reads the tag from the first page view of the visit. If the first page view has no tag, it is not counted for the whole visit. Besides UTM, Openstat, and from, the page lists the service tags yclid, ymclid, ysclid, gclid, yqrid, and yzclid. The contents are recognized correctly when the site’s encoding is UTF-8. This is the first-page-view rule, not an attribution model.

A worked example, not a visit. A person opened the site by a link without yclid, and clicked the ad with the number only on the second page view of the same visit. The tag is not counted for the whole visit: it was not on the first page view. The number may still have been in the URL of the second address. The “Direct” report group will not pick it up as this visit’s tag.

Where an offline conversion is attached

An offline conversion can be written onto a visit by passing a ClientId, a UserId, a yclid, or a PurchaseId, the identifier of a “goal event” goal, and a time in Unix. For yclid the conversion attaches to the visit with that ad, not to the last visit. The data land in the visit if no more than 21 days passed between the visit and the processing of the file. An order from a CRM that is already added to a visit can be changed for another 111 days. The 21 and 111 days are deadlines for supplementing a visit, not a retention period for personal data.

The help calls ClientId the most accurate identifier for offline data: it is a random anonymous browser identifier.

By default Metrica attributes a goal to the visit in which it happened. If a person arrived by an ad without a goal and bought later from search, the conversion goes to search. Through yclid a conversion can be attributed to Direct by hand, including when it happened off the site. The file has to be passed so that no more than 21 days pass between the visit with that tag and the processing. Under the “last click” model some of those visits are not visible in the report, because the ad click was not the last one.