MB Viewer is a free, offline-first desktop application for previewing and editing technical files. Preview TSX/JSX React components without setting up a development environment. Work with Markdown, KaTeX mathematical expressions, Mermaid diagrams, and multiple files in split or quad views. Built for developers, technical writers, researchers, and AI-assisted coding workflows. No account. No cloud dependency. Just open your files and work. Available for Windows, macOS, and Linux.

We built MB Viewer because working with technical files shouldn't require setting up an entire development environment.

During development, we frequently needed to preview React components, inspect Markdown documents, render mathematical expressions, and visualize diagrams. Existing workflows often involved unnecessary setup, dependencies, or online tools.

We wanted something simple, fast, and private — a desktop application that could handle these tasks locally, without sending files to external services.

What started as an internal tool gradually evolved into a standalone application that we decided to share with everyone.

MB Viewer continues to grow, and version 3.0 is a major step forward in that journey.

We built MB Viewer because working with technical files shouldn't require setting up an entire development environment.

We wanted something simple, fast, and private — a desktop application that could handle these tasks locally, without sending files to external services.

What started as an internal tool gradually evolved into a standalone application that we decided to share with everyone.

MB Viewer continues to grow, and version 3.0 is a major step forward in that journey.

MB Viewer

Preview TSX, Markdown and Mermaid files offline instantly

Preview TSX, Markdown and Mermaid files offline instantly