Google Ads has introduced a new bid simulator, the Target ROAS bid simulator. The target ROAS bid simulator shows the relationship between a ROAS target and your key metrics. The key metric it shows is your conversion value.
Google explains; let’s say you’re interested in seeing how a higher target would impact your performance. Using data from the auctions you participated in over the last 7 days, this tool will show you what would have happened assuming everything else (e.g., your ads, landing pages, competitor ads, competitor bids etc.) stayed the same.
Here is a screen shot:
Additionally, Google said on the occasion, you may need to update your budgets for campaigns that use Maximize clicks or Maximize conversions. Like the bid simulator, this new budget simulator will show how these changes could have impacted your performance. This makes it easy for you to find your ideal budget allocation across campaigns.
Forum discussion at Google Ads Help.