The short version: Add up the likes, comments, saves and shares on a post, divide by either your follower count or your reach, then multiply by 100. Do that across ten to thirty posts and average it, and you’ve got a proper engagement rate without paying for a single tool. The bit nobody tells you is that which number you divide by (followers or reach) can make the exact same account look brilliant or mediocre, and most agencies pick whichever one flatters the report.
The formula, written plainly
There are two versions. Use whichever one, but be consistent, because comparing a followers-based rate to a reach-based rate is like comparing miles to kilometres and pretending they’re the same thing.
By followers:
(Likes + Comments + Saves + Shares) ÷ Total Followers x 100
By reach:
(Likes + Comments + Saves + Shares) ÷ Reach on that post x 100
Followers is the number Instagram shows on your profile. Reach is the number of unique accounts that saw the specific post, and you’ll find it under the “View insights” tab on any post if you have a creator or business account. If you’re on a personal account, you only have followers to work with, which is one more reason to switch.
Step by step, with real numbers
Here’s exactly how I do it, using a real post from my own feed as the example.
- Step 1: Pick a post. Mine was a carousel about pricing an AI consultancy package, posted on a Tuesday.
- Step 2: Pull the numbers from Insights. That post got 312 likes, 41 comments, 89 saves, and 22 shares.
- Step 3: Add them together. 312 + 41 + 89 + 22 = 464 total engagements.
- Step 4: My follower count that day was 41,600. My reach on that specific post was 12,900.
- Step 5: By followers: 464 ÷ 41,600 x 100 = 1.11%.
- Step 6: By reach: 464 ÷ 12,900 x 100 = 3.6%.
Same post. Same 464 engagements. One number is 1.11%, the other is 3.6%. If someone hands you an engagement rate without telling you which formula they used, ask, because the gap is not small.
How to build this into a proper habit (not a one-off)
A single post’s engagement rate tells you almost nothing. What matters is the average across a decent sample. When I was rebuilding my business publicly after a rough few years, I tracked every post manually in a spreadsheet for 90 days, no tools, just Insights and a column for date, likes, comments, saves, shares, followers, and reach.
Over that 90 days my follower count moved from 38,900 to 41,200. My average engagement rate by followers was 1.9%. My average by reach was 6.4%. Both are “true.” Neither one alone tells the full story. What told me something useful was watching the reach-based number climb steadily while the followers-based number stayed flat, which meant Instagram was showing my content to more of my existing audience, not that I was suddenly more interesting to strangers.
If you want a longer walkthrough on tracking this kind of thing without a subscription, I’ve written a whole piece on how to measure social media success without a paid analytics tool, which covers the spreadsheet setup in more detail than I have room for here.
What counts as “engagement” (and what quietly doesn’t)
Most calculators, and most people doing this by hand, only count likes and comments. That’s outdated. Instagram’s own algorithm weighs saves and shares more heavily than likes, because a like takes half a second of thought and a save means someone intends to come back to your content. If your manual calculation ignores saves and shares, you’re measuring the laziest form of engagement and missing the two signals that matter most to the algorithm.
Profile visits and link clicks are sometimes included by more advanced calculators, but you can’t get those per-post without Insights, and honestly, for a manual weekly check, likes, comments, saves and shares are enough. Don’t overcomplicate it.
The bit that makes engagement rate a bit of a lie
Here’s the uncomfortable part. A follower-based engagement rate assumes every one of your followers is a real, active person who could theoretically see your post. That’s not true for almost any account over a few thousand followers. Old follow-for-follow accounts from 2019, abandoned accounts, bots that followed you during a giveaway three years ago, they all sit in your follower count dragging your rate down, even though they were never going to engage with anything.
This is why two accounts with identical content quality can show wildly different followers-based engagement rates just because one of them ran a follower-growth campaign in 2021 and the other didn’t. It’s not a measure of how good your content is. It’s partly a measure of how clean your follower list is.
Reach-based engagement rate is more honest because it only counts people who were shown the post. But it’s also easier to inflate, because Instagram sometimes shows a post to a small, highly engaged slice of your audience first, which pumps the percentage before it’s shown more broadly. So even the “more honest” number has its own quiet bias. Anyone telling you engagement rate is a clean, objective metric is selling you something.
What a good engagement rate looks like
The commonly quoted industry benchmark, floating around from various social media reports for years, says 1% to 3% is average and anything over 6% is excellent. Treat that number gently. It’s usually built from a mixed bag of accounts of wildly different sizes, and engagement rate falls almost mechanically as follower count rises, because you can’t keep the same proportion of a crowd engaged as the crowd gets bigger. A creator with 2,000 followers hitting 8% engagement and a brand with 400,000 followers hitting 1.2% might both be doing brilliantly relative to their own history. Comparing them to each other, or to a flat industry average, tells you very little.
What’s useful is comparing your own account to your own past self. Is this month’s average higher or lower than last month’s? Is the reach-based number climbing while followers stay flat, meaning your existing audience is more engaged? That trend line matters more than any single benchmark number.
When manual tracking stops being worth it
Doing this by hand for one account, checking weekly, takes maybe twenty minutes. Doing it across multiple accounts, multiple platforms, or for a client roster, is a different job entirely, and that’s usually the point where people quietly switch to something automated. If you’re at that stage, it’s worth reading through picking a social media marketing tool that won’t waste your money before you buy anything, because most of the tools in this space are built for agencies reporting to clients, not for a solo business owner checking their own numbers.
For agencies specifically, the manual spreadsheet approach falls apart fast once you’re pulling numbers for six or seven client accounts a week, and that’s usually when a proper reporting automation tool for time-starved marketers earns its cost back within the first month, just in hours saved.
Why this number matters more than the algorithm alone suggests
Engagement rate isn’t just a vanity figure for a client deck. A sustained drop in a client’s engagement rate, especially the reach-based version, is often the first visible sign that something’s shifting before they mention cancelling anything to you directly. I’ve seen this pattern with my own retainer clients: engagement quietly softens for three or four weeks, then the “let’s pause things for a bit” email arrives. If you’re managing accounts for other people, it’s worth reading about using AI to spot the clients who are about to leave you, because engagement data is exactly the kind of early signal that pattern-spotting tools are built to catch, well before the cancellation conversation happens.
Building your own quick calculator
If typing the formula into a calculator app every week feels tedious, a simple spreadsheet with the formula built into a cell does the job permanently. Column A is the date, B is likes, C is comments, D is saves, E is shares, F is followers or reach, and column G is just =(B+C+D+E)/F*100. Drag it down and it updates itself for every new post. If you want to go a step further and turn that into something shareable, whether for clients or your own audience, there’s a decent argument for building a proper interactive version, and I’ve covered the thinking behind that in a piece on how to engage and convert more visitors with interactive calculators, which applies just as well to an engagement rate tool as it does to any other calculator you might put on your own site.
A quick worked example you can copy
Say you post five times in a week and want a weekly average.
- Post 1: 90 likes, 8 comments, 15 saves, 2 shares = 115 engagements, followers 5,000, rate 2.3%
- Post 2: 60 likes, 4 comments, 9 saves, 1 share = 74 engagements, rate 1.48%
- Post 3: 140 likes, 22 comments, 31 saves, 9 shares = 202 engagements, rate 4.04%
- Post 4: 45 likes, 3 comments, 6 saves, 0 shares = 54 engagements, rate 1.08%
- Post 5: 88 likes, 11 comments, 19 saves, 4 shares = 122 engagements, rate 2.44%
Add the five rates: 2.3 + 1.48 + 4.04 + 1.08 + 2.44 = 11.34. Divide by 5. Your weekly average engagement rate is 2.27%. That’s the number worth writing down each week, not any single post’s figure.
Frequently asked questions
What counts as engagement on Instagram?
Likes, comments, saves and shares. Saves and shares should carry more weight in your own thinking even though the basic formula treats all four equally, because Instagram’s algorithm rewards saves and shares more heavily than likes when deciding who else to show your content to.
Should I calculate engagement rate using followers or reach?
Use reach if you can get it, because it only counts people who saw the post, which is a fairer measure. Use followers if reach isn’t available to you, but never compare a followers-based rate to someone else’s reach-based rate and assume they mean the same thing, because they don’t.
What’s a good Instagram engagement rate in 2026?
The commonly quoted range is 1% to 3% as average and 6% or above as strong, but this shifts hugely by account size and niche, so your own month-over-month trend matters more than hitting an arbitrary industry number.
Does Instagram calculate engagement rate for you automatically?
No. Instagram’s built-in Insights shows raw numbers, likes, comments, saves, shares, reach, and follower count, but it never does the division for you. You either calculate it manually with the formula above or use a third-party tool that pulls the same raw numbers and runs the same maths.
Where to check the details
Related reading: How Do I Improve Engagement On My Instagram Posts and What Happened With Taylor Swift and the Instagram Engagement Rumours.
For the bigger picture, see my full guide to social media marketing.
