

The Squishify button, right next to Add New Media File on the Media Library screen.
Every major image plugin optimizes images after they’re uploaded — the full-size originals still travel over the wire, still land on your server, and still eat disk space.
Squishify flips the order. Drag a batch of images into the Squishify editor (right inside wp-admin), resize, tune format and quality with a live before/after comparison, and nothing touches your site until you click Upload. Only the finished, optimized files reach your Media Library.
Images are capped at 2560px on the longest edge before encoding — the same threshold WordPress core itself uses (big_image_size_threshold). Because the file you upload is already at or under that size, WordPress never generates its own separate -scaled copy: what you see in the editor is what ends up in your Media Library, one file, no server-side duplicate.
Squishify’s WebAssembly encoders are provided via jSquash (MIT/Apache-2.0), which wraps libavif (BSD-2-Clause), libwebp (BSD-3-Clause), MozJPEG (BSD-style), and Oxipng (MIT) — all GPL-compatible. The .wasm files are unmodified upstream builds.