AI tool comparison
Pretty Fish vs ProofShot
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Pretty Fish
Free, beautiful Mermaid diagram editor that works offline
75%
Panel ship
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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.
Developer Tools
ProofShot
Give AI coding agents eyes to verify the UI they build
67%
Panel ship
—
Community
Free
Entry
ProofShot captures screenshots of running applications and feeds them back to AI coding agents as visual context. Instead of agents blindly writing UI code, they can now see what they built and iterate. Works with browser-based apps and integrates with popular AI coding tools.
Reviewer scorecard
“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.”
“Clean integration — just point it at your dev server and it handles screenshot capture and context injection. The token cost of sending screenshots is non-trivial though, so you want to be selective about when you trigger it. Works best as a verification step, not continuous monitoring.”
“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.”
“Vision models still struggle with subtle layout issues — off-by-one pixel gaps, wrong font weights, slightly misaligned elements. ProofShot catches the obvious breaks but do not expect pixel-perfect QA. You still need human eyes for production UI.”
“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.”
“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 someone who has watched AI agents confidently ship broken layouts, this is a godsend. The visual feedback loop means agents can actually catch that the button is overlapping the nav bar. Design quality from AI coding just leveled up.”
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