In digital marketing, the conversion metrics are - without a doubt - one of the most important metrics to track as it’s directly tied together with your advertisement performance 

I think we all know why, so there is no need to dig further into why it’s important to track conversions for ecommerce companies

In Google Ads, we have 2 different ways of measuring a conversion. 

We are spoiled with 2 metrics that are named: 

1. Conversions 
2. Conversions (by conversion time) 

One of the biggest unlocks in my early Google Ads career was understanding the difference between the “conversion” column and “conversions (by conversion time) as in some cases they could display pretty different data sets. 

And that is exactly what you’ll learn today, as this is one of the most crucial fundamental areas of conversion tracking to master. 

But first, let's talk about conversion lag, and what that is. 

Conversion lag refers to the period between a person clicks on your ads and when the same person completes their purchase 

Conversion lag is very different from product to product and from business to business as it depends on these factors on how long a person is considering purchasing a product from the first click. 

One of the things that are often quite confusing is accounting for conversion lag in your weekly reportings because you can't optimize for smaller windows of data segments as you could be looking at a smaller subset of the complete picture - you could eventually make sure to exclude your conversion lag from your reporting view - so that if we assume that your conversion lag is 7 days, you have to manually exclude the last 7 days in the date selector in Google Ads. 

Or you could look at conversions (by conv. time), conversion value (by conv. time), and ROAS (by conv. time) 

The difference between conversions and conversion (by conv. time) 

But first, let’s start by understanding the difference between the 2 conversion metrics. 

When we refer to “conversions” we are referring to the number of conversions that occurred within the selected date range. The metrics show the number of people who clicked on your ad and converted during the same period. 

For example, if a person clicks on your ad and converts right away on the same day it would count as a conversion 

It gets more tricky when a person clicks on an ad outside of your date range but converts inside your date range - this will ultimately mean that the conversion wouldn't be counted or shown in the conversion column because the conversions are attributed back to when the click happened in the conversion column 

This is illustrated here: 

Here you can see that conversion shows 0 conversion while conversion (by conv. time) shows 1 conversion 

Next, if your conversions click happened on May 25, but the conversion itself happened on June 1, you’ll see a conversion in the conversion column, but zero conversion in the conversions (by conv. time) column. 

Last but not least, if the click happened on May 26th and the conversion happened on May 28th then you’ll see a conversion in both the conversion and conversion (by conv. time) column 

What's the benefit of using conversions (by conv. time) column? 

The conversions (by conv. time) allows you to skip the waiting game for the conversion lag and lets you see a more representative picture of how many conversions your campaigns generated in the selected date range. 

The conversion value (by conv. time) also aligns better with your back-end revenue numbers, which also layers another insight into your reporting. 

Adding conversions (by conv. time) metrics

There are 3 important (by conv. time) metrics that you should add to your reporting: 

1. Conversions (by conv. time) 
2. Conv. value (by conv. time) 
3. ROAS (by conv. time) 

Both conversions (by conv. time) + conversion value (by conv. time) is found natively in the Google Ads columns, but the ROAS (by conv. time) is a custom metric and the formula is.

Conversion value (by conv. time) / cost 

Conclusion

There are multiple benefits of using both conversions metrics, but i have found from experience that the conversions (by conv. time) has given me a better way of evaluating and ultimately steering my campaigns in the right direction.

As with everything is different from business to business how large of a difference there is between the 2 conversion metrics, as it all comes down to how long the conversion lag is and how frequent you are evaluating performance, and in which time-frames you are evaluating performance.