Your latest Instagram post received fewer likes than the previous one. Check its reach before deciding what to change. It may have earned more interactions for every account reached.
To compare the two posts, use the same definition of an interaction and choose a denominator that fits your question.
What counts as an interaction
The feed-post examples here use interactions = likes + comments. Keep that definition unchanged for every post you compare.
You can include saves and shares when those counts are available for every post in the comparison. Label the calculation clearly: a rate based on four actions measures something different from one based on two. Leave unavailable values marked as missing.
Interactions also count actions, not distinct people. One account can like a post and leave several comments. A 5% interaction rate therefore does not mean that exactly 5% of your followers interacted. Instagram distinguishes unique accounts engaged from interaction totals; see this explanation of Instagram Insights metrics.
Choose followers or reach as the denominator
Engagement rate by followers
Engagement rate by followers = interactions ÷ follower count × 100
This measures interactions relative to the size of your following. Record when you measured the follower count. Using today's audience for an old post can change its rate after your account grows.
Engagement rate by reach
Engagement rate by reach = interactions ÷ post reach × 100
Reach counts the accounts that saw the post. This rate expresses interactions per 100 accounts reached. It can include people who do not follow you. Both approaches are established engagement-rate calculations; label the denominator whenever you report a percentage.
If the denominator is zero or unavailable, report the rate as unavailable.
How fewer likes can produce a higher rate
Imagine two organic carousel posts from the same account, each measured seven days after publication. These are illustrative numbers, not customer results.
| Metric | Post A | Post B |
|---|---|---|
| Likes | 450 | 320 |
| Comments | 50 | 40 |
| Interactions | 500 | 360 |
| Followers at measurement | 10,000 | 10,000 |
| Post reach | 10,000 | 4,000 |
| Engagement rate by followers | 5.0% | 3.6% |
| Engagement rate by reach | 5.0% | 9.0% |
Post A generated more interactions and reached more accounts, so it did better on visibility. Post B generated nine interactions per 100 accounts reached, compared with five for A. B is worth reviewing for how people responded relative to its reach, though neither percentage shows which post generated more enquiries or sales.
Try B's topic again while tracking reach and interactions together. You need more than two posts to know whether the pattern repeats.
Make the comparison fair
Compare posts at the same age, such as seven complete days after publication. Selecting posts from the same month does not ensure they have had equal time to accumulate results.
Group posts by format and purpose: compare carousels with carousels and product demonstrations with other demonstrations. Review Stories separately, because replies and navigation actions need different interpretation.
Flag boosted posts and separate paid from organic distribution. A change in audience or advertising spend makes it harder to attribute a result to the content. Use interaction and reach figures with the same scope.
Keep counts beside percentages. Four interactions from 20 accounts reached produce 20%. Give more weight to a sustained pattern across comparable posts with much larger audiences than to this small observation.
Begin with your own comparable posts as a baseline. If you use an industry benchmark, check its formula, formats, account sizes, and reporting period before treating its percentage as a target.
Compare the rates in Smartmetrics
In Smartmetrics' Content view, ordinary feed posts have separate Engagement Rate and Engagement over Reach figures. The former uses followers as its denominator; the latter uses reach. For these posts, the interaction count uses likes and comments. Saves appear separately.
If your spreadsheet includes saves or shares, it uses different inputs from these dashboard figures. Match the inputs before comparing the percentages.
Review the posts alongside their rates. You can also compare distribution alongside response by sorting content by reach. Where the account or post does not provide reach, leave the reach-based comparison unavailable.
Plan the next content test
Choose a small group of comparable posts and record their format, topic, publication date, measurement date, interactions, followers, and reach. Calculate both rates using the same rules.
Write down what you observed. For example: "Our tutorial carousels earned more interactions per account reached than our product announcements during this period." Any explanation is still a hypothesis; topic, timing, distribution, and audience may all have contributed.
Test one change in the next batch and keep the measurement window consistent. Track enquiries or purchases separately if those are your goal. Engagement rate can help you choose a content experiment, but it does not measure those business results.
In Smartmetrics account analytics, review reach and interaction counts alongside engagement rates before deciding what to publish next.