On the path to conversion, customers may interact with multiple ads from the same advertiser. Attribution models let you choose how much credit each ad interaction gets for your conversions.
Attribution models can give you a better understanding of how your ads perform and can help you optimise across conversion journeys.
This article describes the various attribution models and how to use them in Google Ads. You'll learn how to set an attribution model for conversion tracking and bidding, and how to compare models with the 'Model comparison' attribution report.
Benefits
Most advertisers are used to measuring the success of their online advertising on a 'last click' basis. This means they give all the credit for a conversion to the last-clicked ad and corresponding keyword. However, this ignores the other ad interactions that customers may have had along the way.
Attribution models give you more control over how much credit each ad interaction gets for your conversions. This allows you to:
- Reach customers earlier in the purchase cycle: Find opportunities to influence customers earlier on their path to conversion.
- Match your business: Use a model that works best for how people search for what you offer.
- Improve your bidding: Optimise your bids based on a better understanding of how your ads perform.
About the different attribution models
Google Ads currently offers several attribution models:
Last click: Gives all credit for the conversion to the last-clicked ad and corresponding keyword.
Data-driven: Distributes credit for the conversion based on your past data for this conversion action. It's different from the other models, in that it uses your account's data to calculate the actual contribution of each interaction across the conversion path. The 'Data-driven' model is the default attribution model for most conversion actions. Learn more About data-driven attribution.
Example
You own a restaurant called Ristorante Abigaille in Florence, Italy. A customer finds your site by clicking on your ads after performing each of these searches: 'restaurant tuscany', 'restaurant florence', '3 star restaurant florence' and then '3 star restaurant abigaille florence'. She makes a reservation after clicking on your ad that appeared with '3 star restaurant abigaille florence'.
- In the 'Last click' attribution model, the last keyword, '3 star restaurant abigaille florence', would receive 100% of the credit for the conversion.
- In the 'Data-driven' attribution model, each keyword would receive part of the credit, depending on how much it contributed to driving the conversion.
To learn how to compare these attribution models and view how they'd affect your data, check the section on the 'Model comparison' report below.
Your account can contain conversions with the following creditable channels:
- Google paid channels: Google Ads channels can receive credit for a conversion.
- Paid channels: Paid media channels can receive credit for a conversion.
- Paid and organic channels: Both paid and organic channels can receive credit for a conversion.
- [Publisher] channels: Only [publisher] channels can receive credit for a conversion.
- Unknown channels: These conversions are assigned credit by their data source.
About attribution models for conversions and bidding
The 'Attribution model' setting in conversion tracking lets you decide how to attribute conversions for each conversion action. You can use this setting for website and Google Analytics conversion actions. Learn How to find and set an attribution model for your conversions.
This setting affects how conversions are counted in your 'Conversions' and 'All conversions' columns. (Bear in mind that the 'Conversions' column only includes those conversion actions that you've marked as primary conversions).
The attribution model that you choose only affects the conversion action to which it's applied. The setting also affects any bid strategies that use the data in the 'Conversions' column. This means that if you use an automated bid strategy that optimises for conversions, such as target cost per action (target CPA), enhanced cost per click (ECPC) or target return on ad spend (target ROAS), the attribution model that you select will affect how your bids are optimised.
If you use manual bidding strategies, you can change your attribution model to help you set your bids.
If you're not sure what model to choose, check the section below on the 'Model comparison' report, which lets you compare different attribution models. When you're trying a new non-last click attribution model, we recommend that you test the model first and assess how it affects your return on investment.
About the 'Model comparison' report
The 'Model comparison' report lets you compare two different attribution models side by side. To find keywords, ad groups, campaigns or devices that are undervalued on a last-click basis, you can compare the 'Last click' model to the 'Data-driven' model to view the value of keywords as determined by Google AI, which looks at how your customers convert to allocate credit. Data-driven attribution also gives you a sense of the value of ad interactions along the entire conversion path.
Tip: Analyse your CPA or ROAS for different attribution models
You can use the 'Cost / conv'. and 'Conv. value / cost' columns in the 'Model comparison' report to compare your CPA and ROAS for different attribution models. This allows you to identify campaigns or keywords that are undervalued using the 'Last click' attribution model. You can then change your bids based on the actual value of your campaigns and keywords across the full conversion path.
How to find and set an attribution model for your conversions
You can set the attribution model when you're setting up your conversion action, or follow the instructions below to compare attribution models and change the attribution model for an existing conversion action:
Compare attribution models
- In your Google Ads account, click the Goals icon .
- Click the Measurements drop-down in the section menu.
- Click Attribution.
- In the page menu on the left, click model comparison.
- Select an option from the 'Dimension' drop-down menu.
- Use the 'Compare' and 'With' drop-down menus to select the attribution models that you want to view and compare.
You can search for specific keywords, ad groups, campaigns or accounts from the search box above the table.
Change the attribution model for an existing conversion action
- In your Google Ads account, click the Goals icon .
- Click the Conversions drop-down in the section menu.
- Click Summary.
- In the table, select the conversion you want to edit by clicking the conversion name.
- Click Edit settings.
- Click Attribution model, and select an attribution model from the drop-down menu.
- Click Save, then click Finished.
Cross-account conversion tracking
If you use cross-account conversion tracking to track conversions at the manager account level, you must select your attribution model in the manager account.
Attribution models in your reporting columns
When you change the 'Attribution model' setting for a conversion action, it only changes the way that your conversions are counted in your 'Conversions' and 'All conversions' columns going forwards. If you want to see how your historic conversions data would look with the attribution model that you've just selected, you can add the 'current model' columns (located in the 'Attribution' section of the 'Columns' menu):
- Conversions (current model)
- Cost/conv. (current model)
- Conv. rate (current model)
- Conv. value (current model)
- Conv. value / cost (current model)
- Conv. value / click (current model)
- Value / conv. (current model)
These columns can be helpful if you've just changed your attribution model and you want to get a sense of how it will affect your conversion data. You can compare these columns to your regular conversion tracking columns to check how your data would have differed if you'd been using the attribution model you've now selected.
Like the regular 'Conversions' columns, these columns won't include any conversion actions that you've chosen not to mark as primary conversions. However, cross-device conversions are included by default.
Keep in mind that these columns include data that isn't affected by your attribution model selection, such as data from Display Network campaigns using pay for conversions billing.