The JSON viewer
for large files.
Open multi-gigabyte JSON the instant you click it — no frozen browser tab, no “file too large”, no upload. Pandia is a free, native desktop app that streams only the slice on screen, so a 2 GB file opens as fast as a 2 KB one.
Offline · No upload · No file-size limit on opening · Apache-2.0
Most editors choke at a few hundred megabytes. Pandia opens files of any size — hundreds of MB, multiple GB — without parsing the whole tree: lazy zero-copy slicing engages at ≥ 10 MB (backed by sonic-rs) and the UI only ever fetches the slice on screen.
You scroll, search, and navigate instantly — there's no cap on opening or viewing. Only whole-document edit, export and validate materialize the root (a 200 MB ceiling).
Why large JSON files break other viewers
Online JSON viewers and most text editors load the entire file into memory and parse it before they show you anything. That works for a few kilobytes. At a few hundred megabytes the tab freezes; at a gigabyte it crashes or refuses to open the file at all. The data never needed to be parsed all at once — it just needed a tool built for the size.
What you can do with a multi-GB file in Pandia
- View it five ways — Tree, Code, Grid, Graph and Compare, switching instantly.
- Search across the whole document with find & replace, even when only a slice is in memory.
- Filter and sort huge arrays of objects in the Grid like a spreadsheet.
- Navigate the structure without scrolling through millions of lines.
- Export, convert and validate up to the ~200 MB whole-document ceiling.
No size limit on opening
Hundreds of MB, multiple GB — opens instantly, scrolls without lag.
Fully offline
Native Rust + Tauri app. Your file never leaves your machine.
Free & open source
Apache-2.0 for macOS, Windows and Linux. No accounts, no telemetry.
Frequently asked questions
How large a JSON file can Pandia open?
There's no cap on opening or viewing. At 10 MB and up, Pandia switches to lazy zero-copy slicing (backed by sonic-rs) — it opens the file without parsing the whole tree and only ever loads the slice on screen, so hundreds of MB or multiple GB open instantly. Only whole-document edit, export and validation materialize the root, which sets a ~200 MB ceiling for those specific operations.
How do I open a large JSON file without it crashing?
Use a native viewer instead of a browser tab or a text editor. Browser tools load and parse the entire file into the page, so a 1 GB file freezes or crashes them. Pandia is a Rust desktop app that streams the file: download it, drag your JSON in, and it renders the visible portion immediately while the rest stays on disk.
Is my JSON file uploaded anywhere?
No. Pandia is a native desktop app and everything is processed locally on your machine. There are no accounts, no cloud and no telemetry — the only time it touches the network is when you explicitly ask it to fetch a document from a URL.
Does the large JSON viewer work on Mac, Windows and Linux?
Yes. Pandia ships native builds for macOS (Apple Silicon and Intel), Windows 10/11 and Linux. It is free and open source under Apache-2.0.
Stop fighting your JSON.
Download the native app, open your biggest file, and get to work. Free, offline, and open source.