Landscape by Sprout Social - An interactive tool for social media image resizing
Gauguin - Generate dynamic OpenGraph or social images in real-time
OgHero - Generate social share images for your blogs automagically
Bannerbear - Auto-generate IG Stories, Pinterest Pins and more
Robolly - Auto‑personalize your open graph, social posts & more
MightyShare.io - Generate Social Images for WordPress