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Particles UI

What Particles UI is
Particles UI provides design decision infrastructure for teams creating, versioning, reviewing, and publishing design tokens across codebases, themes, and AI agents. Token changes are made on branches and reach the main token set through review. A contrast check blocks merging or publishing when results fall below WCAG AA, and the same check can run in CI. The CLI accepts DTCG, Tokens Studio, CSS, SCSS, TypeScript, and JavaScript token files, and exports formats including Tailwind v4, Style Dictionary, JSON, Flutter, and others. Listed integrations include Figma, Tailwind, GitHub, MCP, and TypeScript. Its MIT-licensed CLI supports local token management and export without an account. The Free plan includes one project, one main branch, three free viewers, unlimited tokens, export formats, releases, version pinning, and limited Figma functions. Pro costs $19 a month for one seat; Team costs $29 per editor per month, and Business costs $79 per editor per month. MCP access requires Team or above. Figma use requires desktop version 116 or later or a Chromium-based browser; Safari is unsupported.
Who it suits
Particles UI suits teams that need review and governance for design tokens across codebases and themes. It may also suit teams that want a CI accessibility gate or local token management through its CLI.
What it does well
- Token changes move through branches and review.
- Contrast below WCAG AA blocks merge or publication.
- The CLI supports multiple token formats and exports.
- Local token management and export work without an account.
- Free plan includes unlimited tokens and export formats.
What to know first
- Free plan Figma access is pull-only.
- MCP access requires Team or above.
- Figma plugin does not support Safari.
- Maker says it is not currently SOC 2 certified.
Limits
The Free plan includes one project, one main branch, and three free viewers; its Figma plugin access is pull-only. Pro is $19 a month for one seat, while MCP access requires Team or above.
Plans
| Plan | Billed and limits | Price |
|---|---|---|
| Free | forever · 1 project · main branch · 3 free viewers · unlimited tokens · all export formats · releases and version pinning · Figma pull, inspect and 1 theme | Free |
| Pro | $19/ month · 1 seat · 5 projects · 5 branches · unlimited themes and Figma variable modes · token graph / DAG explorer · 14-day free trial | $19 a month |
| Team | $29/ editor / month · Token requests, review and 3-way merge · WCAG release gate · webhooks to release-to-PR · MCP and agent recipes · unlimited free viewer seats | $29 a month |
| Business | $79/ editor / month · Multi-level Foundation → Brand → Product · pinned module releases and conflict review · knowledge graph explorer · 4-hour SLA and onboarding · dedicated Slack channel | $79 a month |
As particles-ui.com lists them, read 30 Sept 2026. The maker's own page has the final word.
Getting started
- Visit the Particles UI website.
- Use the MIT-licensed CLI for local token management and export without an account.
- Choose the Free plan for one project, a main branch, and three free viewers.
- Choose Pro, Team, or Business for the listed paid features and capacities.
- For Figma, use desktop version 116 or later or Figma in a Chromium-based browser.
Overview
Particles UI is a token-governance platform for design and engineering teams coordinating shared design decisions across codebases and themes. It suits teams that need changes reviewed before release; its strongest value is pairing that workflow with broad token conversion and an accessibility gate.
Its cloud service combines token management, versioning, code and design-tool sync, governance workflows, and component documentation. The MIT-licensed CLI also supports local token management and export without an account, giving individual developers a useful path that does not depend on the hosted workflow.
For a broader look at this category, see Design System Software.
Key features
Review and accessibility controls
Changes are made on branches and reach the main token set through review, which gives teams a clear checkpoint before shared decisions change. Particles UI says contrast below WCAG AA cannot be merged or published, and the same check can run in CI. That is a meaningful release safeguard, but the WCAG release gate is included with Team rather than the lower-priced Pro plan.
Token exchange across toolchains
The CLI accepts DTCG, Tokens Studio, CSS, SCSS, TypeScript, and JavaScript token files. It exports to Tailwind v4, CSS, SCSS, Style Dictionary, DTCG, JSON, TypeScript, JavaScript, and Flutter. That range makes it a practical fit for teams moving token decisions among design and development environments; teams needing only one format may not benefit as much from its breadth.
Figma and agent workflows
Listed integrations include Figma, Tailwind, GitHub, MCP, and TypeScript. The Figma plugin needs Figma desktop version 116 or later, or Figma in a Chromium-based browser; Safari is unsupported. Free users can pull and inspect tokens but cannot push them, and creating, editing, or deleting tokens in the plugin requires Pro or above.
The MCP server exposes 42 tools for token access, search, impact analysis, WCAG contrast, documentation, releases, and governance. That can support agent-oriented workflows, but MCP access starts at Team, so it is not part of the low-cost entry point.
Security and access
Client traffic to the API uses HTTPS/TLS, and application data is stored in managed PostgreSQL databases. Studio supports GitHub and Google OAuth 2.0 as well as email magic links; organization roles and project-level authorization govern API access. Project webhooks use HMAC-SHA256 signatures, and Stripe handles card data that Particles UI says it does not store as raw card numbers.
Particles UI is not currently certified under SOC 2, PCI DSS, HITRUST, ISO 27001, or SSAE 18. Organizations that require one of those certifications should look elsewhere or confirm that their compliance requirements can be met without it.
Pricing
The Free plan costs nothing, billed forever. It includes one project, the main branch, three free viewers, unlimited tokens, all export formats, releases and version pinning, plus Figma pull, inspect, and one theme. It is a useful way to manage and export tokens, but the single project, absence of branches, and read-only Figma workflow limit collaboration.
Pro costs $19 a month, billed $19/ month, for one seat. It raises the allowance to five projects and five branches, adds unlimited themes and Figma variable modes, and includes a token graph / DAG explorer. A 14-day free trial is offered. Pro fits a solo owner or small team willing to keep governance lightweight; it does not include the Team plan's token requests, review and 3-way merge, WCAG release gate, webhooks, or MCP access.
Team costs $29 a month, billed $29/ editor / month. It adds token requests, review and 3-way merge, the WCAG release gate, webhooks to release-to-PR, MCP and agent recipes, and unlimited free viewer seats. This is the clearest fit for teams needing formal review, accessibility enforcement, or agent connections. Since the price is per editor, costs scale with the number of editors.
Business costs $79 a month, billed $79/ editor / month. It adds a multi-level Foundation → Brand → Product structure, pinned module releases and conflict review, a knowledge graph explorer, a 4-hour SLA and onboarding, and a dedicated Slack channel. It is aimed at organizations needing layered design systems and more support; smaller groups may find Team's governance capabilities sufficient. The free tier and a 14-day trial provide lower-risk ways to evaluate before paying.
Platforms
Particles UI lists Linux, macOS, web, and Windows. Its Figma workflow has the additional browser and version requirements described above, which can rule it out for Safari-based users relying on the plugin.
Who it's for
Choose Particles UI if your team needs a governed token pipeline spanning design and code, particularly when accessibility checks, review, and agent access are part of the release process. The local, account-free CLI also suits developers who want token management and export without adopting the hosted service. It is less suitable for teams that need Figma write access on Free, MCP below Team, or a listed security certification.
Pros and cons
- Pros: Broad import and export format support reduces friction across varied code targets.
- Pros: Branches and review provide a defined route for approving token changes before they reach the main set.
- Pros: Team combines a WCAG release gate with MCP tools and unlimited free viewer seats.
- Pros: The MIT-licensed CLI supports local token management and export without an account.
- Cons: Free Figma access is pull-only, and plugin edits require Pro or above.
- Cons: The WCAG release gate and MCP access require Team, at $29 a month billed per editor.
- Cons: Safari is unsupported for the Figma plugin, which requires desktop version 116 or a Chromium-based browser.
- Cons: It lacks the listed SOC 2, PCI DSS, HITRUST, ISO 27001, and SSAE 18 certifications.
Alternatives
- Zaklad is another freemium option, with Android, iOS, and web platforms.
- Supernova is worth considering for its free plan, which includes up to five seats and one design system.
- Terrazzo is a free option with MIT-licensed open-source tools.
- Bezel offers a free plan with one project, one theme, and up to 1,000 design tokens, though it is not yet open for signup.
- Carbon Design System is an open-source design system with no paid tiers stated.
- Spec Layer has a free plan capped at one Figma file and 10 publishing updates per month.
- UI Vault offers a free core platform with style guides and Figma-powered living guides.
- zeroheight offers a free plan with one editor, one styleguide, one token set, and MCP Standard Search capped at 500 calls per month.
Verdict
Particles UI is a strong choice for design and engineering teams that need controlled token releases across tools, with review and accessibility checks built into the workflow. Its broad format support and local CLI strengthen the case, but the key collaboration and agent features require Team pricing per editor, while Free restricts Figma to pull-only use. Look elsewhere if those costs, the Figma browser requirements, or the absence of specified security certifications conflict with your needs.
Verdict
Particles UI combines token versioning and review with format conversion and an accessibility gate. Note the Free plan's Figma restriction, browser requirements, and the Team-tier requirement for MCP access.
Questions
Is there a free plan?
Yes. Free is billed forever at 0.00 USD and includes one project, a main branch, three free viewers, unlimited tokens, all export formats, releases, version pinning, and limited Figma functions.
How much do the paid plans cost?
Pro is $19 a month for one seat. Team is $29 per editor per month, and Business is $79 per editor per month.
Which platforms does it support?
The listed platforms are Linux, macOS, web, and Windows.
Is any part open source?
The maker says the CLI is MIT-licensed. Local token management and export work without an account.
Can it connect to AI agents?
Its MCP server provides 42 tools for token access, search, impact analysis, WCAG contrast, documentation, releases, and governance. MCP access requires Team or above.
What does the Figma plugin require?
It requires Figma desktop version 116 or later or Figma in a Chromium-based browser. Safari is not supported.
Facts from Particles UI's own pages
- Access control
- Studio supports GitHub and Google OAuth 2.0 and email magic links, while organization roles and project-level authorization control API access. · particles-ui.com, 30 Sept 2026
- Accessibility
- The product says contrast below WCAG AA cannot merge or publish, and the same check can run in CI. · particles-ui.com, 30 Sept 2026
- AI agents
- The MCP server exposes 42 tools for token access, search, impact analysis, WCAG contrast, documentation, releases and governance; MCP access requires Team or above. · particles-ui.com, 30 Sept 2026
- Compliance
- The maker says it is not currently certified under SOC 2, PCI DSS, HITRUST, ISO 27001 or SSAE 18. · particles-ui.com, 30 Sept 2026
- Figma plan limits
- Free plan users can pull but not push tokens, and creating, editing or deleting tokens in the plugin requires Pro or above. · particles-ui.com, 30 Sept 2026
- Figma requirement
- The Figma plugin requires Figma desktop version 116 or later or Figma in a Chromium-based browser; Safari is not supported. · particles-ui.com, 30 Sept 2026
- Imports and exports
- The CLI accepts DTCG, Tokens Studio, CSS, SCSS, TypeScript and JavaScript token files and exports formats including Tailwind v4, CSS, SCSS, Style Dictionary, DTCG, JSON, TypeScript, JavaScript and Flutter. · particles-ui.com, 30 Sept 2026
- Integrations
- The maker lists Figma, Tailwind, GitHub, MCP and TypeScript among the stack integrations. · particles-ui.com, 30 Sept 2026
- Open source
- The maker says its CLI is MIT-licensed and local token management and export work without an account. · particles-ui.com, 30 Sept 2026
- Payments and webhooks
- Project webhooks use HMAC-SHA256 signatures, and Stripe handles card data that Particles UI says it does not store as raw card numbers. · particles-ui.com, 30 Sept 2026
- Token governance
- Changes are made on branches and reach the main token set through a review process. · particles-ui.com, 30 Sept 2026
- Transport and storage
- Client traffic to the API uses HTTPS/TLS, and application data is stored in managed PostgreSQL databases. · particles-ui.com, 30 Sept 2026
- What it does
- Particles UI provides design decision infrastructure for teams to create, version, review and publish design tokens across codebases, themes and AI agents. · particles-ui.com, 30 Sept 2026
Where Particles UI stands on Freedom251
- Design System Software#4 of 22