About Conversion Optimiser

  • The goal of Conversion Optimiser is to get you the most conversions given your cost-per-acquisition (CPA) goals. Rather than focusing on clicks (CPC) or impressions (CPM), Conversion Optimiser focuses on maximising conversions.
  • With Conversion Optimiser, you can set either a maximum cost-per-acquisition (Max. CPA), which is the most that you're willing to pay for each conversion, or a target cost-per-acquisition (Target CPA), which is the average amount that you'd like to pay for a conversion.
  • Conversion Optimiser will focus either on conversions or converted clicks depending on the conversion bid metric that you choose on your conversion settings page.
Conversion Optimizer

How Conversion Optimiser works

Using historical information about your campaign, Conversion Optimiser automatically finds the optimal equivalent CPC bid for your ad each time it's eligible to appear. You still pay per click, but you no longer need to adjust your bids manually to reach your conversion goals.


Angela sells new and vintage concert T-shirts online. She had been successfully using contextual targeting to reach potential customers while they spend time on music blogs and read online entertainment magazines, but she thought that there was still room for improvement. So, she decided to try Conversion Optimiser.

Angela knew that, on average, she'd like to pay £5.00 for a conversion on her site, so she set this as her Target CPA bid and then let Conversion Optimiser do the rest. A few weeks later, Angela checked in on her campaign's performance. She was pleased to discover that her conversion rate had improved by more than 0.5%!

Here are some examples of likely ways Conversion Optimiser accomplished this increase:

  • It found that, over time, a blog about '80's bands drove conversions at a high cost by sending Angela many clicks that weren't translating into conversions. Bid levels for this site were automatically lowered until Angela's ads stopped appearing on this website, thus freeing up budget for higher performing websites.
  • It found that, across the board, Angela's ads received clicks at lower costs on sites with a heavy metal band theme. In addition, clicks from visitors to these websites resulted in a high percentage of conversions. So Conversion Optimiser made sure to bid successfully on even more Display Network sites related to heavy metal bands.
About recommended bids

Conversion Optimiser provides you with a recommended Max. CPA bid and a recommended Target CPA bid to help get you started. It's best to use one of these recommended bids when you first start because these bids are calculated to help to ensure a smooth transition to your new bidding mode. From this starting point, you can observe your performance and adjust your bid accordingly.

As with CPC bidding, the CPA bid you set is your primary control over how many conversions you'll get and how much you'll pay for them. You can raise your CPA bid if you want to increase traffic and conversions. If your average CPA is higher than you prefer, you can lower your bid, which will probably decrease both the average CPA and the number of conversions. Learn how to adjust your CPA bid

Requirements for Conversion Optimiser

You'll need to meet the following requirements to begin using Conversion Optimiser:

  • Your campaign uses AdWords Conversion Tracking or cross-account conversion tracking or is importing data from Google Analytics.
  • The campaign should usually have received at least 15 conversions in the last 30 days. This conversion history enables the system to make accurate predictions about your future conversion rate. So, the more data we have, the more accurate we can be. In some cases, you may be able to use Conversion Optimiser without campaign history if you already have conversion data elsewhere in your account.

Bear in mind

  • Conversion Optimiser bids will be used instead of any bid adjustments that you’ve set (except where you’ve set a mobile bid adjustment of -100%). Note that you don’t need to remove bid adjustments - they just won’t be used.
  • Conversion Optimiser automatically accounts for differences in conversion rates across devices, days, times and locations.
  • If one of your ad groups is using both Conversion Optimiser and remarketing lists for search ads (RLSAs), then the bid set by Conversion Optimiser will be used instead of any RLSA-related bid adjustments. However, your bids will be optimised based on whether people are on your remarketing lists.
  • Conversion Optimiser can't be used with Shopping campaigns.
  • Separate Display Network bids can't be used with Conversion Optimiser. Conversion Optimiser automatically optimises your bids across the Search and Display Networks.
Increase your campaign's conversions

Here are some ideas for increasing the number of conversions in your campaign:

  • If you're willing to spend more on your advertising, and you're currently hitting your budget on a regular basis, you can increase your budget.
  • If you're willing to spend more on your advertising, but you're not hitting your budget, you can increase your CPC bids for the ad groups in the affected campaign. Higher bids help to increase your Ad Rank, which leads to greater visibility for your ad. With more visibility, you're likely to get more clicks that lead to conversions.
  • If you prefer to keep your costs the same, consider moving the conversion tracking code on your website. For example, Jean runs an insurance website. Her tracking code is on the page a customer reaches after signing up for an insurance policy. She decides to move the tracking code to the page that provides insurance quotes. The conversion data from this page is still meaningful for her business, and her conversions increase because more customers reach this page than the "Thank you" page. If you move your conversion tracking code, make sure that you wait two weeks before turning on Conversion Optimiser to allow the system time to adjust.
  • Combine your campaign with another campaign for a related product that has a similar conversion rate. You can use AdWords Editor to copy and paste ad groups between campaigns. If you make this kind of major change to your campaigns, make sure that you wait two weeks before turning on Conversion Optimiser to allow the system time to adjust.
  • Opt in to the Google Display Network.
  • Add more relevant keywords to your ad groups.
  • Change your ads or landing page to try to increase your click-through rate (CTR) or conversion rate.

In addition, the following campaign characteristics can help to increase conversions:

  • The campaign is direct-response oriented. For example, the campaign focuses on generating sales on an e-commerce website.
  • The campaign has a well-defined conversion type, such as a completed purchase or signup.
  • The campaign has a relatively stable conversion rate, with no major changes (such as redefining the conversion event or moving the conversion tracking code) within the last two weeks.
Tips for Conversion Optimiser success
  • Start with the recommended CPA bid. Set either a Max. CPA or Target CPA bid based on which metric is most familiar to you.
  • Raise your Max. or Target CPA bid to increase traffic and conversions. Lower your Max. or Target CPA bid if you want to lower your average CPA. Traffic will most likely decrease.
  • We recommend not changing the CPA bid more than once every few weeks. This will give you time to account for any conversion delays and give Conversion Optimiser time to adjust.
  • Use Conversion Optimiser with existing campaigns. The longer a campaign has used conversion tracking and the more conversions it’s received in the past 30 days, the more data Conversion Optimiser can draw upon to make predictions.
  • Bear in mind that changes in ad performance are natural, and you may need to use Conversion Optimiser for some time to get an accurate understanding of its effects on your campaign's performance.
  • Don't make huge changes to a campaign while running Conversion Optimiser, for example, removing all ad groups and replacing them with new ones. Do make small changes to your campaign that fit your business needs, for example, adding/removing keywords, changing creative, changing landing page.
  • Don't remove your conversion tracking code from your website or move it to a different location while running Conversion Optimiser. Doing either of these could result in significant changes in which clicks lead to reported conversions. As a result, Conversion Optimiser may need up to several weeks to adjust to these changes.
  • Compare your CPA and conversion rate before and after using Conversion Optimiser to gauge its impact on your campaign.
  • Remember, you can always turn off Conversion Optimiser, and your campaign will revert to the previous CPC bids that you were using.
  • If you're consistently hitting your budget, increase it to allow more visibility for your ads.
Using Conversion Optimiser effectively for mobile app campaigns

If you're running a campaign to promote mobile app downloads, Conversion Optimiser can help you get the most downloads for your budget. Here are some suggestions for setting up your campaign:

  1. When you launch your mobile app promotion campaign, avoid overly restrictive campaign settings (too much location targeting, for example) that could reduce your traffic.
  2. Keep track of your performance over the first two weeks, then exclude sites and categories that aren't reaching your goals.
  3. Once you've optimised your campaign and reached a sustainable CPA, begin using Conversion Optimiser and set a Target CPA that's consistent with your performance to date. Note that download conversion tracking is only available for advertisers promoting Android apps and for existing users of the AdMob iOS translation service.
  4. Use these targeting methods to further refine your traffic:
    • Target new devices
    • Add interest categories to your ad groups to reach people interested in products and services similar to those your business offers
    • Use advanced ad scheduling for specific days of the week and hours of day
Changes in traffic or conversion rate

Changes in traffic

If you notice a drop in traffic (clicks and conversions) after turning on Conversion Optimiser, there could be a few things going on:

  • Your CPA bid might be too low. If you're using a Target CPA bid, compare your bid to the historical average CPA of your campaign. If your bid is significantly below your historical average CPA, your Target CPA may not be attainable while maintaining reasonable levels of traffic, and you should consider raising your bid.
  • Instead of conversions, you may be looking at clicks or impressions. Because Conversion Optimiser aims to get you more conversions by avoiding traffic that doesn't result in conversions, you may see a decrease in impressions or clicks while increasing the number of conversions.
  • Conversion Tracking is disabled. If you remove conversions that you're tracking, then the ads in campaigns using Conversion Optimiser will stop running. To start showing your ads again, you'll need to enable Conversion Tracking or switch to manual bidding.
  • Your ad group is missing a CPA bid. If your ad group doesn't have a CPA bid, then the ads in this ad group will stop showing while in Conversion Optimiser. To start showing your ads again, you'll need to set an ad group CPA bid or switch to manual bidding.

Changes in conversion rate

It's possible to see a drop in conversion rate when you start using Conversion Optimiser. This change may occur because you're observing an average of the conversion rate across all clicks. For example, suppose Conversion Optimiser causes your campaign to have an increase in very cheap clicks with slightly lower conversion rates. If there were no other changes in your campaign, this change in conversion rate would appear as a decrease. However, the change in cost could have a very positive effect on your campaign's ROI.


Let’s say you used to get one conversion out of every 10 clicks from a specific website, and each click cost £1. This would mean that you have a 10% conversion rate with a total cost of £10 per conversion. Then, let's say that Conversion Optimiser changed your bids so you that advertised on a website where you paid £0.10 per click, but that only one in 50 people converted from these. Your conversion rate would drop to just 2%, but your cost per conversion would also drop to just £5.

Did you know...

Conversion Optimiser looks at all Conversion (AdWords) and/or imported Goal Tracking data (Google Analytics), but it weighs recent data more heavily.

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