New · Slint MCP server + llms.txt — build native UIs with Cursor, Claude Code & Copilot
Pricing & licensing

Free to start.
Fair as you grow.

Open source · Royalty-free for desktop, mobile & web · Commercial & support available

Three licenses

Pick the one that fits

Not sure? Will your app be open source?

GPLv3Fits you
€0/ forever

Build open-source software on any platform, embedded included.

  • All platforms, embedded included
  • Full open-source UI toolkit
  • Your whole app must be open source
  • Community support

Perfect for OSS, research & evaluation.
GUI Test Framework & Support available as add-ons.

Use GPLv3
Royalty-FreeFits you
€0/ forever

Ship proprietary apps on desktop, mobile & web. Just credit Slint.

  • Desktop, mobile & web
  • Closed-source products allowed
  • No royalties, no per-seat fees
  • Community support

Embedded isn't covered, see GPLv3 or Commercial.
GUI Test Framework & Support available as add-ons.

Start free

The Commercial license

One license, priced for your size

Smaller and younger companies pay less. Each level bundles a little more.
Prices shown in your local currency where available.

Startup & Individual
from €9/ mo

Individuals, or companies under ~10 staff / €2M and < 5 years old.

  • Ship proprietary on every platform
  • Community support

Add on: Standard Support · GUI Test Framework · Perpetual Fallback · Premium SLA

Buy now
Small Enterprise
from €90/ mo

Companies under ~50 staff / €10M turnover or balance sheet.

  • Everything in Startup & Individual
  • Standard Support included

Add on: GUI Test Framework · Perpetual Fallback · Premium SLA

Buy now
Enterprise
from €380/ mo
  • Everything in Small Enterprise
  • Standard Support included
  • GUI Test Framework included
  • Perpetual Fallback (12-mo rolling)

Add on: Premium SLA support

Buy now

Eligibility follows the EU SME definition (plus the <5-year rule for Startup & Individual).
Every level covers all platforms, the difference is what's bundled.

Side by side

What each license gives you

GPLv3 Royalty-Free Commercial
CostFreeFreeFrom €9/moby company size
PlatformsAll incl. embeddedDesktop · mobile · webAll incl. embedded
Proprietary / closed-sourceNo — copyleftYesYes
Community support
Standard SupportAdd-onAdd-onIncluded¹
Premium (SLA) SupportAdd-onAdd-onAdd-on
GUI Test FrameworkAdd-onAdd-onIncluded²
Perpetual FallbackIncluded²

¹ Included from Small Enterprise; an add-on for Startup & Individual.  
² Included with Enterprise; an add-on for smaller Commercial levels.

Tailor it

Support & add-ons

Mix and match. Most add-ons are available to the free licenses too.

Support
Community
Free
Everyone
Standard
€90/ mo
Or bundled with Commercial
Premium
SLA
Available to anyone
Get support
GUI Test Framework
€163/ mo

Automated UI testing for Slint.

Bundled with Enterprise. An add-on for GPLv3, Royalty-Free and the smaller Commercial levels.

Buy now
Perpetual Fallback
€163/ mo

Keep a perpetual right to the release from 12 months prior, rolling forward as you renew.

Commercial-only.

Buy now

Why pay at all?

Commercial licenses fund Slint.

Slint is built by a company, not a side project. Open source keeps it accessible; Commercial licenses keep it funded, maintained and improving. If Slint earns its keep in your product, a Commercial license is how you keep it healthy.

Straight answers

Licensing, without the fog

How is the Commercial license priced?

By company size, following the EU SME definition: Startup & Individual (individuals, or micro companies under 5 years old), Small Enterprise, and Enterprise. It's the same license on every platform — smaller companies simply pay less. Prices are monthly, shown in your local currency where we support it.

What's bundled vs. an add-on?

Startup & Individual includes the right to ship + community support. Small Enterprise adds Standard Support. Enterprise adds the GUI Test Framework and Perpetual Fallback. Anything not bundled at your level can be bought as an add-on.

Is desktop, mobile and web really free?

Yes — Royalty-Free covers those three for proprietary products at no cost. You'd only pay if you want support, the Test Framework, or to ship on embedded — or simply to fund Slint via a Commercial license.

Can I use the Commercial license for desktop, mobile or web?

Yes — Commercial covers every platform. On desktop, mobile and web you can choose Royalty-Free (free, with Slint attribution) or Commercial (no attribution, plus support and the Test Framework). Both keep your application source closed.

Is the GUI Test Framework free?

It's bundled with Enterprise. For GPLv3, Royalty-Free and the smaller Commercial levels, it's a paid add-on.

What's the Perpetual Fallback License?

After 12 months of continuous payment, you hold a perpetual right to the release from 12 months prior — and it rolls forward as long as you keep subscribing. Stop, and you keep the last version you'd earned, so you're never stranded. Commercial-only.

Do I keep my own source code?

Under Commercial and Royalty-Free, yes: your application code stays closed. Under GPLv3 your own files can keep any GPL-compatible license (MIT, BSD, and so on), but the combined app is distributed under GPLv3 with complete source, so it can’t stay proprietary.

Still not sure?

Tell us what you're shipping.

Two minutes and you'll know exactly which license you need — and what it costs.

Open source forever · keep your source · cancel anytime