Based on our record, UI Filler seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Working link: https://uifiller.com (I don't know how to make it a link in the body of the post). - Source: Hacker News / almost 2 years ago
Placemat - Pretty nice placeholder images.
Humaaans - Mix-&-match illustrations of humans with a design library.
Placeholder Loader Creator - SVG component editor to create placeholder loaders
Handsome Illustrations - Create unique illustrations for websites & applications.
placeholder.pics - Lightest way to include placeholder images in your design
Blush - Illustrations for everyone