Fractional Conversions

What Are Fractional Conversions?

When you see conversion numbers like 2.7 in Google Ads, those are fractional conversions from data-driven attribution. This model is more honest than last-click because it realistically maps each campaign’s contribution. For campaign optimization, this means: don’t evaluate individual campaigns in isolation — understand how they work together to generate conversions.

Fractional conversions occur when Google Ads uses the data-driven attribution model (DDA) and distributes a single conversion proportionally across multiple clicks or campaigns. Instead of a whole conversion of 1.0, you see values like 0.3 or 0.7 in your reports. These decimal values reflect the estimated contribution of each touchpoint to the conversion path.

The underlying principle makes sense: if a user first clicks a brand ad, then sees a generic ad, and finally converts via a remarketing ad, each touchpoint had a share in the success. DDA distributes the conversion accordingly. The challenge in practice is that many advertisers calculate with whole numbers, and decimal values in reporting and budget decisions can cause confusion.

For correctly interpreting fractional conversions, aggregate your reports at the campaign level, where fractions add up to meaningful totals. At the keyword level, individual fractional conversions can be misleading. Also note that conversion modeling adds estimated conversions on top, which also appear as decimal values. Separate modeled from observed conversions in your analyses to get a clear picture.