The best metrics to measure success on TikTok Ads will depend on your specific business goals and objectives. Here’s a brief overview of some common metrics used to measure success on TikTok Ads:

1. Return on Advertising Spend (ROAS): This metric measures the revenue generated from your ad spend. It’s calculated by dividing the revenue generated by the cost of the ad campaign.
2. Return on Investment (ROI): This metric measures the overall return on your investment, including both the revenue generated and the cost of the ad campaign. It’s calculated by dividing the revenue generated by the total cost of the investment.
3. Customer Acquisition Cost (CAC): This metric measures the cost of acquiring a new customer. It’s calculated by dividing the total cost of the ad campaign by the number of new customers acquired.
4. Click-through rate (CTR): This metric measures the number of clicks on your ad per number of impressions. It’s calculated by dividing the number of clicks by the number of impressions.
5. Cost per thousand views (CPM): This metric measures the cost of your ad campaign per thousand views. It’s calculated by dividing the total cost of the ad campaign by the number of views, and multiplying by 1000.

It’s important to keep in mind that these metrics are not mutually exclusive, and it’s recommended to track multiple metrics to get a comprehensive view of your campaign’s performance. Additionally, depending on your business goals, some metrics may be more important to track than others. For example, if your goal is to acquire new customers, CAC would be a key metric, if your goal is to drive revenue, then ROAS would be a key metric.