Engagement Rate Calculator: Instagram ER and the Posts That Beat It
Is this creator’s engagement good for an account of their size, and which of their posts actually worked? Engagement Rate Calculator answers both on the profile itself. Open any Instagram profile and a small badge in the corner shows its engagement rate. Click it and a side panel opens with the rest.
The panel has the engagement rate by followers with a typical range for an account of that size, reel views and engagement by views, posting pace, and the posts themselves, ranked by outlier score: how many times a post beat the creator’s own typical post. A reel at 6× did something the other reels did not, and that is usually the one worth studying. The same score shows as a badge on each tile of the profile grid. You can narrow the list to the last 7, 30 or 90 days, export it as CSV, or copy the top posts with a prompt to ask an AI what their hooks have in common.
What counts as “typical”
The posts a visitor sees, not the newest dates. Engagement rate is averaged over the first 12, 33 or 66 posts of the grid, without pinned ones. Version 0.1 took the newest posts by date instead, and on one profile the rate slid from 4.95% to 2.66% as more posts loaded: creators move old posts to the top, and a window by date kept shifting. The grid’s order does not change as more loads.
A baseline that leaves out what would skew it. The outlier score divides a reel’s views, or a photo’s likes and comments, by the median of the 25 newest posts that are at least three days old, without pinned posts and paid partnerships. A post from yesterday is still collecting likes, and a paid partnership is not the creator’s usual post. With fewer than eight such posts there is no score, and the panel says so instead of guessing.
No server
Everything is computed in the browser. The extension reads the answers Instagram already sends the page, and for older posts it repeats the page’s own next-page request, one at a time, at least a second apart. Nothing is sent anywhere, and there is no account to make.
Try it
Engagement Rate Calculator is free in the Chrome Web Store; the Firefox version is on its way. If a number disagrees with what you see on a profile, write to me at anton@kopylov.net.