Follower Growth Calculator
Growth split into gained and lost, annualised by compounding, with what the growth did to the engagement rate.
Followers at the start of the month 18,400
gained +1,240
lost -380
Followers at the end 19,260
Net growth, the month 4.674%
annualised, compounded 73%
not 56.1%, the rate multiplied by 12
Unfollow rate 2.065%
Gained for every one lost 3.26
At this rate
doubles in 15.2 months
after 3 months 21,102
after 6 months 24,202
after 12 months 31,833
What happened to engagement
engagements before 4,200 across 12 posts
engagements after 4,310
change 2.6%
engagement rate before 1.902%
engagement rate after 1.865%
reading the rate fell, so the new followers engage less: more reach, thinner audience
Net growth is 4.674%, from 1,240 gained against 380 lost. The net figure
alone would hide both: an account gaining a lot and losing a lot is a
different thing from one gaining steadily, and the ratio between them,
3.26, is the number worth tracking.
Annualised that is 73% rather than 56.1%. Growth compounds, so
multiplying a monthly rate by 12 understates it, and the gap widens with
the rate.
Engagement rate falls when an account adds followers who do not engage,
even while total engagement rises. Which of those two you care about
depends on the objective: reach wants the bigger number, community wants
the rate.
Follower count is the metric most easily bought and least connected to
anything. A thousand followers cost a few dollars, and they engage with
nothing, so a jump in the count with no change in engagement is worth
checking rather than celebrating.
Unfollows are information. A spike usually follows a specific post, a
change in posting frequency, or a partnership that did not suit the
audience, and the platform will usually tell you which day it happened.
Growth from a small base is mostly noise. Going from 200 to 260
followers is 30 percent and 60 people; the same rate at 200,000 is a
different achievement. Ask for the absolute number alongside the
percentage.
Reach and followers have come apart on every platform that shifted to
recommendation feeds. A post now reaches people who do not follow the
account, which means follower count constrains reach much less than it
used to and predicts it much worse.
Output is valid and updates as you type.
Fix the highlighted fields to update the output.
Gaining 1,240 followers and losing 380 is 4.67 percent growth. The net figure alone hides both numbers, and the ratio between them, 3.26 gained for every one lost, is the more informative one.
The figure that matters even more is what happened to engagement while the count grew. Engagement rate is engagements over followers, so an account that adds followers who do not engage sees the rate fall while the total rises. On the example below, engagement went up 2.6 percent and the rate went down: more reach, thinner audience. Which of those you want depends on the objective, and reporting only the follower count settles the question by accident.
How to use
- Put in the follower count at the start, then how many were gained and lost.
- Pick the period. Monthly and weekly both annualise by compounding here, not by multiplying.
- Add the engagements before and after to see what the growth did to the rate.
Example
Followers at the start of the month 18,400
gained +1,240
lost -380
Followers at the end 19,260
Net growth, the month 4.674%
annualised, compounded 73%
not 56.1%, the rate multiplied by 12
Unfollow rate 2.065%
Gained for every one lost 3.26
At this rate
doubles in 15.2 months
after 12 months 31,833
What happened to engagement
change 2.6%
engagement rate before 1.902%
engagement rate after 1.865%
reading the rate fell, so the new followers engage less: more reach, thinner audiencePitfalls
Do not multiply a monthly rate by twelve. 4.674 percent a month compounds to 73 percent a year, not 56. The error grows with the rate.
A net figure hides the unfollows. An account gaining 4,000 and losing 3,000 looks the same as one gaining 1,100 and losing 100. The second is healthier at a lower net number, and only the split shows it.
Engagement rate falling is not automatically bad. It means the audience grew faster than the engagement, which is what happens when a post reaches beyond the existing following. Whether that is dilution or reach depends on what you are trying to do.
Follower count is the easiest metric to buy. A thousand followers cost a few dollars and engage with nothing, so a jump in the count with flat engagement is worth investigating rather than celebrating.
Unfollows are information. A spike almost always follows a specific post, a change in frequency, or a partnership that did not suit the audience, and the platform will usually show you which day.
Growth from a small base is noise. 200 to 260 is 30 percent and sixty people. The same rate at 200,000 is a different achievement, so ask for the absolute number too.
Reach and followers have come apart. Recommendation feeds show posts to people who do not follow the account, which means the follower count constrains reach far less than it used to and predicts it much worse.
Compatibility
Arithmetic in the browser: nothing is uploaded and nothing is stored.
Growth is net over the starting count, and annualising raises (1 + rate) to the number of periods in a year,
with the multiplied figure printed next to it because that is the mistake this exists to prevent. The
unfollow rate is losses over the starting count, which is the convention, and it is not the same as the churn
of an audience that joined during the period.
The engagement comparison divides engagements per post by the follower count at each end, so it compares like with like even when the posting frequency stays the same. A change in posting frequency between the two periods makes the comparison meaningless, which is why the post count is an input.
Loss of followers greater than the starting count plus the gains is refused, since that cannot happen.