Open Source Image Editor
The trap with an image editor is that its real power lives in a working file: the layers, masks, and adjustments saved in a project format, and that file is worthless the day a future version or a defunct vendor cannot open it. So the format you edit in is the actual commitment, more than any single tool. It also helps to notice that this one label covers very different crafts, since developing raw photos, retouching, digital painting, vector and interface design, and AI upscaling have little in common. The open source editors here keep their working files in documented, readable formats and run on your own machine, so a years-old project still opens and your originals never leave your disk.
Excalidraw
Open source virtual whiteboard for hand-drawn style diagrams, wireframes, and collaborative sketches
Penpot
Open-source design platform for teams, with self-hosting and open standards like SVG, CSS, HTML, and JSON
Upscayl
Free and open source AI image upscaler for Linux, macOS, and Windows
ShareX
Free and open source Windows app for screen capture, recording, and file sharing
Graphite
Free open source vector and raster editor with nondestructive layers and a node-based procedural engine
darktable
Photography workflow app and non-destructive raw developer for organizing and editing digital negatives
Krita
Free and open source digital painting app for creating artwork, comics, illustrations, and concept art
PixiEditor
Universal 2D editor for pixel art, painting, vectors, and animation in one app
GIMP
Free and open source image editor for retouching, compositing, and creating graphics
Our picks
These cover four distinct crafts that all get called image editing, so match the pick to the work rather than ranking them.
General photo editing and compositing: GIMP A broad, cross-platform editor for retouching photos, compositing images, and creating graphics. It offers layers and masks, customizable brushes, and a deep set of color correction tools, and you can reshape the interface with themes, CSS, and your own shortcuts. Plug-ins and scripts automate repetitive tasks or add capabilities, which suits it to production pipelines.
Digital painting: Krita A dedicated painting app for creating artwork from blank canvas to finished render, aimed at professionals and serious hobbyists rather than general editing. A deep, customizable brush engine, layers, masks, and color management give the control needed for comic pages, illustration, concept art, and matte, texture, and VFX painting.
Nondestructive raw development: darktable A photography workflow app and raw developer that keeps your digital negatives in a database, so you browse, develop, and export without altering the originals. A zoomable lighttable rates and sorts a collection while the darkroom fine-tunes each shot, and finished images export to local or remote storage. Optional AI modules stay off by default.
Vector graphics: Inkscape A vector drawing tool for illustrations, icons, logos, diagrams, maps, and web graphics, built for artwork that needs editable shapes and output that scales cleanly. It uses the W3C open standard SVG as its native format, so files stay readable in other tools rather than locked to one app.
Choosing an image editor by the work you do
Photographers, painters, and designers reach for completely different tools, even though all three end up called image editors. A raw workflow like darktable or RawTherapee is about developing camera files nondestructively, with the original negative left untouched, and that is a different job from GIMP or Pixelitor retouching a layered composite, or Krita and MyPaint chasing brush latency and pressure response for painting. Vector and interface work belongs to Inkscape or Penpot, and enlarging a small image is a job for a dedicated upscaler like Upscayl. Pick the model that matches your actual work before comparing feature lists, because the seams show under deadline.
Treat file format support as the main risk rather than a checkbox. Opening a PSD, TIFF, or raw file is not the same as preserving every layer effect, mask, text object, and color profile, so if you exchange files with people on commercial tools, test round trips with real production files first. For photography, decide whether raw development is integrated or handed to a separate step, since a tool like darktable keeps edits as instructions over an untouched original while pixel editors bake changes in. For print, verify ICC profiles and soft proofing before you trust a CMYK export.
Finally, check input and automation on the machines you really use. Large layered images stress memory before CPU, and brush feel changes with each tablet driver and display, which matters for long painting or masking sessions. If you process many product shots or thumbnails, scriptable batch export matters more than another filter, and command-line upscalers such as waifu2x-ncnn-vulkan exist precisely for that kind of bulk job. A strong plugin system can extend an editor, but core edits that depend on an unmaintained add-on become a fragility you inherit.
Related categories
Frequently asked questions
Which of these develop raw photos, and which edit pixels?+
They are different jobs. darktable, RawTherapee, and Filmulator are raw developers: they turn camera files into finished images nondestructively, keeping the original negative untouched and edits stored as instructions. GIMP, Pixelitor, and Pinta are pixel editors that work directly on raster layers for retouching and composites. Krita and MyPaint are painting apps focused on brushwork. Many people use a raw developer first, then hand a rendered file to a pixel editor for cleanup.
Will an open source editor open my Photoshop PSD files correctly?+
Basic raster layers have the best chance of surviving, but PSD is a complicated interchange format. Text, smart objects, adjustment layers, layer effects, masks, and embedded color profiles can shift or be rasterized on import. GIMP and Pixelitor both handle layered files, but before you migrate anything important, build a test folder of typical production files and compare both appearance and editability after opening and re-saving, not just the thumbnail.
Which are best for digital painting with a drawing tablet?+
Painting apps live or die on brush feel and tablet support. Krita has a deep, customizable brush engine with layers, masks, and color management, and is built for comics, illustration, and concept art. MyPaint centers on an infinite canvas and configurable, paint-like brushes with extensive tablet support and a distraction-free workspace. PixiEditor adds pixel art and animation. Test pressure, tilt, and brush latency on your own tablet, since driver and display setup change how each one feels.
Can I upscale a low-resolution image without uploading it anywhere?+
Yes, several tools run AI upscaling entirely on your own machine. Upscayl runs Real-ESRGAN models on a Vulkan GPU across Linux, macOS, and Windows, with a command-line tool for batch jobs. waifu2x-ncnn-vulkan is a GPU command-line upscaler and denoiser that processes whole directories. On Windows, RealScaler and QualityScaler handle both images and video offline. None require an account or a connection, so source files never leave your disk.
Is any of these suitable for professional print and CMYK work?+
Print work needs more than a CMYK export button. Check ICC profile support, soft proofing, black point handling, and whether color conversions stay predictable across machines. Some of these editors are aimed at screen graphics rather than prepress, so if you need spot colors, separations, or a printer-specific PDF handoff, run a real proof with your actual print vendor before committing a job. Verify that embedded profiles survive the export you plan to send.
Which handle vector or interface design rather than photo editing?+
For work that needs editable shapes and clean scaling, reach for a vector tool instead of a raster one. Inkscape uses W3C SVG as its native format for illustrations, icons, logos, and diagrams. Penpot is a design and prototyping platform built on open standards like SVG, CSS, and HTML, with self-hosting and real-time collaboration. Graphite combines vector and raster with a nondestructive, node-based workflow, and Akira targets native Linux UI and UX design.
What happens to my work if the editor's project is abandoned?+
The risk is almost always the native project format, not your exported PNG or JPEG. Keep final deliverables in standard formats and archive layered work as documented formats like TIFF when you can. Editors built on open standards age best: Inkscape saves plain SVG and Penpot uses SVG, CSS, and HTML, so those files stay readable in other tools. Save a known-good installer, note any required plugins, and periodically test that another editor can open your source files.