AI tool comparison
Bolt.new vs Pretty Fish
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Bolt.new
Prompt to full-stack app in your browser
67%
Panel ship
—
Community
Free
Entry
Bolt.new by StackBlitz lets you describe an app in natural language and generates a full working prototype — frontend, backend, database — all in a browser-based dev environment.
Developer Tools
Pretty Fish
Free, beautiful Mermaid diagram editor that works offline
75%
Panel ship
—
Community
Free
Entry
Pretty Fish is a free, open-source Mermaid diagram editor with live preview, 5 built-in themes, multi-page workspaces, and one-click SVG/PNG export. It works offline as a Progressive Web App (PWA) and requires no account, no login, and no installation. It supports all 14+ Mermaid diagram types including flowcharts, sequence diagrams, Gantt charts, entity-relationship diagrams, and Git graphs. The editor includes syntax highlighting, auto-completion, instant error feedback, and a clean split-pane layout. The multi-page workspace lets you manage entire diagram projects in a single session. Export quality is excellent — SVG output is clean and scaling-ready for use in presentations, docs, or design systems. Pretty Fish hit Hacker News front page today with 128 points and has the makings of the go-to Mermaid editor for developers who generate diagrams from AI-assisted documentation workflows. With LLMs increasingly generating Mermaid syntax in their outputs, having a polished renderer and editor matters more than ever.
Reviewer scorecard
“Perfect for prototyping. I described a dashboard and had a working app in 3 minutes. Not production-ready, but unbeatable for speed-to-demo.”
“The official Mermaid live editor is clunky and slow. Pretty Fish loads instantly, works offline, and the multi-page workspace means I can manage all my architecture diagrams in one place. Bookmarking this immediately as my default Mermaid editor.”
“Impressive demo, but the generated code is messy and you'll rewrite most of it. If you can't code, you can't fix what it breaks. Know what you're getting into.”
“It's a genuinely nice editor but it's solving a niche problem — most devs who need Mermaid diagrams already use VS Code extensions or embed them in Notion. And with no backend, there's no collaboration or sharing story, which limits its use in team workflows.”
“As a creator who needs quick landing pages and MVPs, this is a game-changer. I built a waitlist page with email capture in under 5 minutes.”
“Five beautiful themes and clean SVG exports mean I can finally use Mermaid diagrams in client-facing presentations without them looking like developer scratch notes. This is the Mermaid editor I've always wanted and the zero-friction setup seals it.”
“As AI tools increasingly output Mermaid syntax to explain architectures and flows, the need for a great rendering environment grows. Pretty Fish positions itself at the intersection of AI-generated diagrams and human editing — that's a well-timed niche.”
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