Various metrics can be used to accurately gauge the reach of an influencer marketing campaign on platforms like Flinque. These can include:

1. Impressions and Reach: These metrics indicate how many users have seen the campaign content at least once.

2. Engagement Rate: This tracks how many people interacted with the campaign’s content, through actions like comments, shares, likes, and more. It’s a good indication of how well the content resonated with the audience.

3. Audience Growth Rate: This shows how the campaign has helped in expanding the influencer’s audience base.

4. Click-through rate (CTR): Insight into how many people took the desired action (such as visiting a website) after viewing the campaign content.

5. Brand sentiment: Analyzing comments and feedback can give an idea of the audience’s perception of a brand after the campaign.

6. Conversion Rate: Reflects how many people completed the desired action, like making a purchase, signing up, etc.

While other platforms provide similar metrics, the way they collate and present this information can differ. As for Flinque, it prides itself on its intuitive and easy-to-understand dashboard which presents all these metrics in real-time and in easy-to-understand terms. Remember that the utility of different analytics can depend on the specific goals of your campaign. Therefore, always align your performance metrics with your campaign objectives for an accurate measurement of ROI.