To find the right mobile bid, you would calculate:
(mobile conversion rate / desktop conversion rate) + 1
(mobile conversion rate / desktop conversion rate) x 100
(desktop conversion rate / mobile conversion rate) – 1
(mobile conversion rate / desktop conversion rate) – 1
Explanation:
Find Computer conversion rate and mobile conversion rate using Estimated Total Conversions column. Divide mobile conversion rate by computer conversion rate -1
Read more here: https://support.google.com/partners/answer/6209121?hl=en
Just as with desktop AdWords campaigns, mobile campaigns use bidding and targeting to determine where and when your ads show up. A click may be worth more to you if it comes from a mobile device or a specific location, or at a certain time of day. By setting bid adjustments, you can increase or decrease your bids to gain more control over when and where your ad is shown.
Bid adjustments
A bid adjustment represents a percentage change in your bids. You can increase or decrease every bid in your campaign to bid more or less competitively across devices, locations, times of day, and more. You can also adjust your bids based on how your ads perform, helping to improve your return on investment (ROI).
Your spending on individual clicks may vary as your bids increase or decrease according to the adjustments you’ve set, but your overall daily budget won’t change.
How to set up mobile bid adjustments
Increasing or decreasing the role mobile plays for each campaign allows you to capitalize on success and reduce waste. Use conversion data to assess which channel drives more value.
When conversion data shows that mobile drives more value, increase your mobile bid to capitalize on mobile success. Alternatively, when conversion data shows that desktop drives more value, turn down your mobile bid based on the difference.
Set your mobile bid based on the value mobile generates. Find this by dividing your mobile conversion rate by your desktop conversion rate. Follow the steps below:
From the Campaigns tab, click Segment and choose Device
Choose campaigns with enough data for consistent results (90 days and more than 20 conversions on both Mobile and Computer)
Find Computer conversion rate and mobile conversion rate using Estimated Total Conversions column.
Divide mobile conversion rate by computer conversion rate -1
For example:
Mobile conversion rate = 4.43%
Computer conversion rate = 3.96%
(4.43% / 3.96%) -1 = 0.118 = 12%
For this example, the best way to capture the most value from mobile is to set the mobile bid adjustment at +12%.