Mermaid vs Whimsical

Mermaid

• Developers who already write Mermaid syntax in docs or Markdown
• Teams that want diagrams versioned and reviewed as text
• People who want AI to draft a diagram from a document or transcript
• Showing diagrams as slides without exporting them

Whimsical

• Product teams sketching flows, wireframes and specs in one place
• Teams with many occasional viewers, since only editors are billed
• Linux users: the desktop app ships as DEB and RPM packages
• Students and teachers, who can apply for a free year

Mermaid

• The free Basic plan is listed as 3 diagrams on its plan card and up to 6 in the comparison table, with a limited diagram size and 15 AI credits.
• Paid plans are billed annually only; the vendor's FAQ says monthly plans are not available.
• AI credits are capped at 300 a year on Plus and 2,000 a year on Premium; only Enterprise is listed as unlimited.
• Free viewer seats start at Premium, and SSO, invoicing and a customer success manager are limited to Enterprise.

Whimsical

• The Free plan allows 50 new board objects and 50 doc blocks a month and puts a watermark on exports.
• There is no dedicated mobile app: on a phone, files can be viewed and commented on in a browser, and iPad use is browser-based.
• AI credits are a one-off 10 per account on every plan; more are sold in bundles starting at 250 credits for $25.
• Private teams, SAML single sign-on and SCIM are limited to Business, at $20 per editor / month billed annually.

Mermaid

Diagrams from Mermaid code

Diagrams are written in Mermaid syntax and laid out automatically. Clicking a node jumps to its code and clicking the code finds its shape, so the two stay in step.

Mermaid AI

A description, an uploaded document or a pasted transcript becomes a first-draft diagram, and the AI suggests a fitting diagram type. Use is metered in credits below Enterprise.

Visual Editor

Nodes, edges, labels, colors and shapes can be changed by clicking and dragging while the code rewrites itself, with node alignment and movable edges for tidying a layout.

Live co-editing and share links

Teammates can co-edit a diagram at the same time, and a share link lets other people view it without logging in. Free viewer seats are part of Premium and Enterprise.

Plugins and MCP server

Plugins cover VS Code, JetBrains IDEs, Cursor, Windsurf, Confluence, Jira, Google Docs, Word and PowerPoint. An MCP server lets Claude, VS Code and Cursor generate diagrams.

Presentations

Existing diagrams become slides written in Markdown. A deck updates when its diagrams change and can be shared through a public link for viewing and comments.

Whimsical

Boards on an infinite canvas

One board type covers flowcharts, mind maps, sequence diagrams, sticky notes and freehand sketches. Voting and a timer are included on every plan.

Wireframes

Wireframes are assembled from drag-and-drop components, as a quick way to explore product ideas and iterate on them.

Whimsical AI

A prompt generates a flowchart, a branched mind map or an editable wireframe. Each account gets 10 one-off AI credits; more are sold separately at $0.10 each.

Docs

Docs hold notes, project plans, briefs and specs next to the boards they describe, with Markdown support, toggles and embedded content.

Multiplayer editing and comments

Several people can edit a file at once and leave comments on it. Share links can grant view, comment or edit access on every plan.

Embeds and AI tool connectors

Boards embed live in Notion and Obsidian and preview in Slack, Jira and Google Docs. An MCP server and connectors let ChatGPT, Claude and Cursor create diagrams.

Mermaid

• Basic$0

  3 diagrams with a limited diagram size, 15 AI credits, and one team and project. Co-editing and external sharing are included.

• Plus$10

  per user / month, billed annually ($120 a year)

  Unlimited diagrams with no size limit and 300 AI credits per year, for individuals who diagram often.

• Premium$20

  per user / month, billed annually ($240 a year)

  Everything in Plus, plus 2,000 AI credits per year, unlimited free viewer seats, and unlimited teams and projects.

• EnterpriseCustom

  Everything in Premium, plus SSO, custom contracts and invoicing, IP management, user consolidation and a dedicated customer success manager.

Whimsical

• Free$0

  50 new board objects and 50 doc blocks a month, 5 MB uploads within 1 GB of storage, watermarked exports and 7-day version history.

• Pro$10

  per editor / month, billed annually ($12 billed monthly)

  Unlimited board objects and doc blocks, exports without a watermark, 90-day version history, password-protected files and 100 GB of storage.

• Business$20

  per editor / month, billed annually ($24 billed monthly)

  Private teams, SAML single sign-on, SCIM, content security lock, unlimited version history, invoicing, priority support and storage from 2 TB.

Mermaid

No public discounts listed.

Whimsical

• Annual discount

  2 months free with annual billing

  Pro is $120 per editor billed annually against $12 a month, and Business is $240 against $24. The pricing page shows this as a 17% saving.

• Education

  Free for a year for students and teachers

  Teachers and students can apply for the education plan, which provides the same features as Pro free of charge for a year.

• Nonprofit

  20% off for nonprofits

  Whimsical offers a 20% discount to non-profit organizations that apply through its form.

• Other savings

  Free for life for YouTube creators

  Creators with a public YouTube channel of at least 1,000 subscribers and a video published in the past 30 days can apply for a plan that is free for life.