Instagram Social Analytics
Simply Measured is a social analytics tool. Their Instagram Account Report provides clear stats and insights on the number of your posts, the breakdown of post types (e.g. video and photo), total engagement, engagement per post, the number of likes per photo, and how your overall performance is trending. It'll also help identify keyword mentions in the comments, filters that are performing best, locations of your top-performing posts, and the best days and times to engage with your audience.
The tool basically gives you a comprehensive overview of how effective your Instagram efforts are, what you have to change, and what exactly worked and should be repeated in future.
Available options: Simply Measured offers a free Instagram report for users with up to 25,000 followers.
Free version: https://simplymeasured.com/free-social-media-tools/
Source: Social Media Today | 5 Free Tools and Apps for Instagram Marketing