Drop JSON file here, or click to select
100MB+ Support · Browser-side Processing · No Upload
Web Worker Parsing
Non-blocking UI
Virtual Scroll Tree
Millions of nodes
Browser-only
No data upload
About JSON Big Viewer
JSON Big Viewer is a free online JSON viewer that supports parsing and browsing ultra-large files (100MB+). All processing is done locally in your browser — your data is never uploaded to any server. Supports JSON formatting, minification, validation, search, and conversion to CSV, SQL, TypeScript, and more.
How to Use
Upload Your JSON File
Drag and drop, select, or paste your JSON data directly into the browser. Files up to 100MB+ are supported.
Browse the Tree View
Explore your JSON data with an interactive tree view. Expand and collapse nodes to navigate nested structures easily.
Search, Format & Convert
Use the toolbar to search keys or values, format or minify JSON, validate syntax, or convert to CSV, SQL, and TypeScript.
Download Results
Download your formatted JSON, conversion results, or select specific objects from NDJSON files for export.
Features
Web Worker Parsing
JSON parsing runs in a background Web Worker thread, keeping the UI responsive even with massive files. No freezing, no blocking.
Virtual Scroll Tree View
Efficiently render millions of JSON nodes with virtual scrolling. Only visible nodes are rendered, ensuring smooth performance.
Full-Text Search
Search across all keys and values in your JSON. Navigate between matches instantly with highlighted results.
Format Conversion
Convert JSON to CSV, SQL (CREATE TABLE + INSERT), TypeScript interfaces, and JSON Schema — all in your browser.
NDJSON Support
Parse and browse Newline Delimited JSON files. Select specific objects to download or export individually.
100% Client-Side Processing
Your data never leaves your device. All parsing, formatting, and conversion happens entirely in your browser. Zero server uploads.
Why Choose JSON Big Viewer
Lightning Fast
Web Worker-based parsing and virtual scrolling ensure instant response times, even with files containing millions of nodes.
Complete Privacy
Your data stays on your device. Zero server uploads, zero tracking. Ideal for sensitive or confidential JSON data.
Massive File Support
Handle JSON files of 100MB+ without breaking a sweat. Optimized memory usage and streaming parsing for real-world large files.
100% Free
No registration, no limits, no ads. A fully free tool built for developers who work with JSON daily.
Multi-Format Export
Convert JSON to CSV, SQL, TypeScript, and JSON Schema in one click. Perfect for data migration, API development, and analysis.
Open Source
Built with Next.js, React, and TypeScript. Fully open source and transparent. Inspect the code, contribute, or self-host.