Photo by Markus Spiske on Unsplash

UPDATED 2021-06-13:

This article now includes all Kickstarter campaigns that launched from 2020-01-01 and ended by 2021-05-07. The significant increase in sample sizes has resulted in major changes to the approach, and moderate changes to the outcome, of our original analysis. Portions of this article have been rewritten to reflect those changes.

Introduction

Not too long ago, I answered the question “What’s the best day of the week to launch on Kickstarter?”. In this post, I’d like to cover a related question that you might not have thought of: “What’s the best day to end a Kickstarter campaign?”

Arguments

Although it’s not as hotly debated as the best day to launch, it’s still pretty easy to find opinions and arguments on what day is the best day to end a campaign. General consensus is that Thursday is the best. In fact, Kickstarter itself claims that the best launch/end combination is Tuesday/Thursday, although they offered up no real reason for why that might be.

Personally, I don’t think what day you end on really makes any difference. If Thursday has the highest success rates, I’d guess that’s only because of how closely associated it is with Tuesday launches. Of course, what I think doesn’t really matter – let’s look at the data!

Analysis

Thursdays are the most popular day to end Kickstarter campaigns, which isn’t too surprising.

Chart showing that Thursday is the most popular day to end a campaign on Kickstarter

The more important metric, however, is what the success rates are for each end day. Here we see that Thursdays do, in fact, have higher success rates. However, those rates could be due to any number of factors that have nothing to do with choosing that day to end. If we don’t account for those factors, we may end up falsely attributing success to something that makes no real difference.

Chart showing that, without accounting for confounding factors, Thursday appears to be the best day to end your Kickstarter campaign.

What are those confounding factors? Well, they turned out to be the same ones that were confounding success rates vs launch day. I won’t go into great detail here, since I already did in that post, but the confounding factors I was able to identify were:

  • Day of the week that the campaign launched
  • Proportion of campaigns that were virtually guaranteed success
  • Proportion of campaigns that were virtually guaranteed to fail
  • Proportion of campaigns that were tabletop games

The only notable difference in confounding factors between end day and launch day is the proportion of first-time creators. There isn’t any particular end day that has more or less first-time creators than any other. As such, there wasn’t a strong enough case to consider it a confounding factor. Apart from that though, these two analyses are the same.

So, after accounting for all of those factors, what day ends up being the best day to end a Kickstarter campaign?

Results

Chart showing that Thursday's success rates are within the confidence interval of other week days.

Turns out there really isn’t a clear leader for the best day to end a campaign. We can say with confidence, however, that Thursday is better than Sunday, Tuesday, and Saturday. We know that because the confidence intervals (the purple shaded region) for those days do not overlap with Thursday’s at all.

As for the other days? We really can’t say, because their shaded regions overlap at least by a small amount. So, for instance, because Wednesday’s interval overlaps both Thursday’s and Tuesday’s, we don’t know if Thursday is better than both Tuesday and Wednesday, or if Wednesday and Thursday are both better than Tuesday. We’re just not exactly sure where Wednesday falls. The same goes for any other days whose intervals overlap. All we can say is that, if you have a choice between Sunday, Tuesday, Thursday, or Saturday, Thursday is the best option.

Now, we’ve shown that Thursday is a better day to end than Sunday, Tuesday, or Saturday. The question now is: by how much? For that, we can again turn to the confidence intervals. Let’s take Thursday and Tuesday as an example. By looking at the confidence intervals, we know that Thursday should be better than Tuesday by, at least, the difference between Thursday’s lower bound and Tuesday’s upper bound, and no more than the difference between Thursday’s upper bound and Tuesday’s lower bound.

So what is that range? Anywhere from 0.8 to 6.0 percentage points. Not exactly earth shattering, but hey, every little bit helps, right?