Both pitch themselves as serious, non-destructive Photoshop replacements with layers, masks and blend modes — Compositor as a free, open-source, Mac-only agent-friendly editor, Affinity by Canva as the long-running professional suite that just went free too, making the two the obvious free-vs-free Photoshop-alternative comparison.
The verdict
Pick Compositor if you're on an Apple Silicon Mac with macOS 26, want a free open-source editor, and plan to script or AI-edit PNG layer folders directly.
Pick Affinity by Canva if you need Windows or iPad support, CMYK and RAW workflows, or want a mature, professionally maintained editor backed by a large company.
At a glance
| Compositor | Affinity by Canva | |
|---|---|---|
| Price & account | free, open source, no account | free app, AI behind Canva Pro |
| Platform & setup | Apple Silicon, macOS 26 only | Mac, Windows; iPad coming |
| Maturity & file support | new, single-dev, no CMYK | mature, pro-grade, full CMYK |
| AI & automation | agents edit PNG+manifest live | AI gated behind Canva Pro |
Side by side
Price & account
Compositor is completely free and open source under the MIT license, downloadable from GitHub Releases or Homebrew with no account or sign-in required.
Affinity by Canva is now free for individuals with every editing tool unlocked, but it requires a free Canva account to download and run, and its AI features (generative fill, background removal) only unlock with a paid Canva Pro subscription.
Platform & setup
Compositor runs only on Apple silicon Macs with macOS 26, a brand-new requirement that excludes Intel Macs and older macOS versions entirely.
Affinity by Canva runs natively on both Apple silicon and Intel Macs as well as Windows, with an iPad version already announced as coming soon.
Maturity & file support
Compositor is a brand-new, single-developer project whose PSD import only supports 8-bit RGB (not CMYK) and whose vector/vertical text support is limited, converting unsupported elements to pixels.
Affinity by Canva: Affinity has years of development behind Serif's professional suite, with full CMYK workflow, RAW processing, frequency-separation retouching, and a mature plugin ecosystem used by working photographers and studios.
AI & automation
Compositor: Any AI agent or script can read and write a Compositor project directly, since a .comp is just a folder of PNG layers plus a manifest that updates live while open.
Affinity by Canva: Affinity's AI tools (generative fill, expand & edit, background removal) only activate for Canva Premium subscribers and are not designed for external agents to script against.
Links
- Compositor: https://github.com/robbietilton/Compositor
- Affinity by Canva: https://www.affinity.studio/
- This comparison on Telegram: https://t.me/SkipCI/193
FAQ
When should I pick Compositor over Affinity by Canva?
Pick Compositor if you're on an Apple Silicon Mac with macOS 26, want a free open-source editor, and plan to script or AI-edit PNG layer folders directly.
When should I pick Affinity by Canva over Compositor?
Pick Affinity by Canva if you need Windows or iPad support, CMYK and RAW workflows, or want a mature, professionally maintained editor backed by a large company.