Photopea

Photopea is a remarkably capable, browser-based image editor that closely mimics Adobe Photoshop's interface and supports PSD, XCF, and Sketch files. It includes layers, masks, smart objects, and a wide range of filters and adjustments. It runs entirely in your web browser with no installation required. Targeted at students, casual users, or professionals needing quick edits on any computer, it is free with optional ads or a premium ad-free version.

It scores highly for its astonishing depth as a web app, excellent file format compatibility, and providing a near-complete Photoshop-like experience instantly and for free.