The most effective Pinterest pin size in 2025 is still 1000 x 1500 pixels, that’s a 2:3 aspect ratio, which works best for mobile visibility and user engagement. It fills more screen space vertically without getting cut off. Pins with this format also tend to get better outbound click rates compared to wider or square formats.
That said, Pinterest doesn’t punish other sizes, but if you want maximum performance, stick with 1000×1500 and make sure your design is clean, scroll-stopping, and readable on mobile.