Format Express is a free universal online formatter that beautifies minified or malformed JSON, XML, HTML, SQL, stack traces, and other data formats for developers dealing with logs and APIs.

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🚀 Overview

Format Express is a lightweight, browser-based tool that instantly formats dense, minified data from sources like API responses, console outputs, or logs into readable, interactive structures. It excels at handling 'noisy' or malformed inputs without strict validation, saving developers time on everyday debugging tasks.

What problem does this project solve? Reading and navigating unformatted structured data is tedious and error-prone; Format Express makes it effortless with syntax highlighting, tree navigation, and search.

Who is it built for? Developers, engineers, and ops folks who frequently paste data into tools for inspection.

Why did you build it? Created by Christophe Boulet to address real-world needs in web services and logging, it has evolved since ~2020 based on practical usage and feedback.

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✨ Key Features

• Universal Formatting: Supports JSON (HJSON, PHP serialized), XML/HTML, SQL, YAML (viewer), stack traces (Java/C#), tabular data, Unix commands; permissive with malformed input, unescapes, cleans noise.
• Interactive Viewer: Syntax highlighting, expandable nodes, minimap, breadcrumbs, regex search, keyboard navigation (arrows, jumps), dark mode.
• Customization & Tools: Settings for indentation, alignment, unicode unescape, XML trimming; beta HTTP API for CLI/curl, URL fetch (CORS), Diff Express, image/SVG previews, date hovers.
• Privacy & Performance: No data saved/logged (except link API 10 days), up to 8MB inputs, lightweight (<512KB).

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🛠 Tech Stack

• Frontend: Vanilla JavaScript (client-side processing, highly optimized)
• Backend: Minimal custom server (for beta API)
• Database: None
• Auth: None
• Hosting: Custom (format-express.dev)

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👥 Who Is This For?

This project is useful for:

• Developers who want to instantly prettify logs, API payloads, or SQL dumps
• Teams looking for a free, no-install, private formatter
• Engineers building or debugging web services needing quick data exploration

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📸 Screenshots / Demo

• Live demo: https://format-express.dev
• GitHub: N/A

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🔥 Project Status

• 🟢 Actively building

Last updated: 2026-03-24

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❓ FAQ

Is this project free?

Yes — fully free to use, donations appreciated to cover server costs.

Is the source code available?

No — source code is not publicly available.

Can I contribute?

No formal process; share feedback or suggestions via the creator's LinkedIn or Stack Overflow profile.

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📬 Contact & Links

• Website: https://format-express.dev
• GitHub: N/A
• Twitter/X: N/A
• Email: N/A
• LinkedIn: http://fr.linkedin.com/pub/christophe-boulet/a/313/28a
• Stack Overflow: http://stackoverflow.com/users/1128103/baldrick

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