Everybody knows that vertical images look and perform better on Pinterest than horizontal images. The official guide from Pinterest recommends using photos with aspect ratios between 2:3 and 1:3.5. This is a very broad range though. When you are trimming a photo or designing a pinnable infographic, you have to pick an exact aspect ratio.
There are plenty of opinions on the internet on which aspect ratio perform the best, but we did not find any studies that would show the exact correlation between aspect ratio and pin performance. So, we went ahead and conducted our own research. The chart below shows the average repin ratio for pins with different aspect ratios.
Frankly, we were quite surprised with the results of this study. We expected the ideal aspect ratio to be somewhere in the middle of the range recommended by Pinterest (between 2:3 and 1:3.5). But after analyzing a statistically significant sample of pins we discovered that extra long pins with aspect ratio of 1:5 perform even better than the tallest pins that Pinterest recommends (1:3.5).
Another potentially helpful observation is that the chart has a local maximum around 1:1.5. So, if there is no way to make an extra tall pin from your image, your next best option might be the 1:1.5 aspect ratio.
Happy pinning from BoardBooster!