Principle

Name: Principle
Price: 129 USD

Free trial iPhoneMacSelf-hostedWeb

What Principle is

Principle is a paid tool for designing animated, interactive interfaces for web, mobile, and desktop. Its timeline lets you set animation timing and easing, including spring animations. Prototypes can respond to dragging, scrolling, paging, taps, and hover events. You can map multi-screen app flows and view an overview of the screens. Principle imports designs from Figma or Sketch and can merge later imports with existing work. Share to Web creates a private browser link that opens on Windows, macOS, Linux, Android, and iOS. Designs can be exported as a self-hostable HTML file, video, or animated GIF. The native macOS app runs on Intel and Apple Silicon Macs. The maker presents it for evaluating interface ideas before engineering and communicating prototypes to engineering teams. A 14-day trial counts only days used. The license is for one computer; new features after the first year require renewal.

Who it suits

Principle suits designers planning interactive interface concepts, multi-screen flows, and animated prototypes before engineering work. It also fits teams that need browser sharing or exports for engineering communication.

What it does well

Timeline supports custom easing and spring animations
Interactions include dragging, scrolling, taps, and hover
Imports Figma and Sketch designs
Exports HTML, video, or animated GIF
Private browser sharing works across listed platforms

What to know first

Paid product with no free plan
License applies to one computer
New features after year one require renewal
Support replies may take at least a week

Limits

The trial lasts 14 days of actual use. The $129 a month license covers one computer, and features released after the first year require the $99 a month renewal to access.

Plans

Plan	Billed and limits	Price
Principle license	Per computer; includes new features released within one year of purchase · Continued use after one year; renewal required for new features	$129, paid once
License renewal	Per computer · Renews an existing license	$99, paid once

As principle.app lists them, read 8 Oct 2026. The maker's own page has the final word.

Getting started

Open the Principle website
Start the 14-day trial
Install or use Principle on a listed platform
Import designs from Figma or Sketch
Create screens, animations, and interactions
Share through a private web link or export your design

Verdict

Principle combines animation controls, interaction prototyping, screen-flow views, imports, sharing, and exports in one tool. Check the one-computer license and renewal terms before choosing it.

Questions

How much does Principle cost?

The Principle license is $129 a month for one computer. License renewal is listed at $99 a month per computer.

Is there a free plan or trial?

There is no free plan. The full version has a 14-day trial counting only days you actually use it.

Which platforms does Principle support?

Listed platforms are iOS, macOS, self-hosted, and web. The native desktop app runs on Intel and Apple Silicon Macs.

Can Principle import existing designs?

Yes. It imports designs from Figma or Sketch and can intelligently merge work when designs are imported again.

How can prototypes be shared or exported?

Share to Web provides a private browser link. Designs can also be exported as a self-hostable HTML file, video, or animated GIF.

What happens after the first license year?

The license can continue to be used, but features released after the first year require renewal.

Facts from Principle's own pages

Animation: Its timeline lets users customize animation timing and easing, including spring animations. · principle.app, 8 Oct 2026
Desktop platform: Principle is a native macOS app that runs on Intel and Apple Silicon Macs. · principle.app, 8 Oct 2026
Export: Principle can export a design as a single self-hostable HTML file, a video, or an animated GIF. · principle.app, 8 Oct 2026
Free plan: No · principle.app, 21 Sept 2026
Imports: Principle can import designs from Figma or Sketch and intelligently merge work when designs are imported again. · principle.app, 8 Oct 2026
Intended users: The maker describes Principle as a way to evaluate interface ideas before engineering work and communicate prototypes to engineering teams. · principle.app, 8 Oct 2026
Interactions: Prototypes can use interactions such as dragging, scrolling, paging, taps, and hover events. · principle.app, 8 Oct 2026
License limit: A license applies to one computer, and new features released after the first year require renewal to use. · principle.app, 8 Oct 2026
Multi-screen flows: Users can design multi-screen app flows and see an overview of their screens. · principle.app, 8 Oct 2026
Purpose: Principle is a tool for designing animated and interactive user interfaces for web, mobile, and desktop. · principle.app, 8 Oct 2026
Sharing: Share to Web creates a private shareable link that opens in a browser on Windows, macOS, Linux, Android, and iOS. · principle.app, 8 Oct 2026
Support: The maker says Principle is a one-person company and that replies to messages may take at least a week; help is also available through its community forum and documentation. · principle.app, 8 Oct 2026
Trial: The full version is free to try for 14 days, counting only days the user actually uses it. · principle.app, 8 Oct 2026