JSON Viewer

  • Worker-parsed
  • 50 MB+ ready
  • Nothing uploaded

Explore JSON as a collapsible tree — built for files that freeze other viewers.

Input
Tree

Paste input on the left to see tree.

Everything runs in your browser — nothing is uploaded.

About tree viewer

A JSON viewer opens a JSON file as a collapsible tree so you can explore its structure instead of reading raw text. JSONic parses in a Web Worker and renders only the rows currently on screen, so files in the tens of megabytes stay responsive. Search keys and values, expand to a depth, and copy any node's JSONPath.

Paste or drop a JSON file and explore it as a collapsible tree. Parsing runs in a background worker and the tree renders only the rows currently on screen, so multi-megabyte documents open without freezing the tab. Search jumps to matching keys and values and expands the path to reach them, every node exposes a copyable JSONPath, and detected values such as URLs, colours, dates and base64 images get an inline preview.

Questions

How large a JSON file can this viewer open?

Files in the tens of megabytes open comfortably. Parsing runs in a Web Worker and the tree only renders the rows inside the viewport, so cost scales with what you look at rather than with file size. Above 4 MB the editor switches to a read-only view, because browsers cannot keep an editable textarea that large responsive.

Is my JSON uploaded to a server?

No. Every operation runs in your browser. Nothing is transmitted, logged or stored server-side.

Why does this open files that other JSON viewers cannot?

Most viewers build a DOM node for every value in the document, so a million values means a million elements. JSONic keeps a flat row model and mounts only the visible rows, and it never re-serialises the document to compute statistics.