Open Structured Data Files

safe · secure · no server · works offline · fast

…or just start typing at the cursor.

↓ scroll for about & FAQ

Open any structured-data file — without uploading it

Drop a structured-data file and OmniViewer detects its format and opens the best available toolkit. Common formats get specialized views; everything else can still be edited or inspected in hexadecimal — all in your browser, with no upload and no server.

Formats with a dedicated toolkit

JSON — format & validate, convert to YAML or CSV, a node graph, an editor, stats and hex.
CSV & TSV — an aligned table, an in-browser SQL engine, CSV→JSON, per-column stats, editor and hex.

TOML, NDJSON, HAR and other structured formats open in the universal viewer — line-numbered text with an editor, plus a byte-exact hex view — and HAR continues into the JSON toolkit. Whichever you drop, the whole file is read locally, so even a multi-gigabyte export opens privately.

FAQ

Is my data file uploaded anywhere?

No. OmniViewer is a static page with no server-side processing: your file is read directly by your browser and never leaves your computer.

Which structured-data formats are supported?

JSON and CSV/TSV have dedicated toolkits (formatting, conversion, SQL, a graph, per-column and structural stats). TOML, NDJSON, HAR and other structured files open in the universal editor and hex viewer, and HAR continues into the JSON toolkit. Format is detected from the content, not the extension.

How large a file can I open?

Effectively unlimited. The raw and hex views read only the bytes needed to paint the screen, so they open a 20 GB file as readily as a 2 KB one; the engine behind them has been tested in-browser with a 40 GB file.