Data converter · runs 100% in your browser

BSON to JSON Converter

Convert MongoDB's binary BSON format to readable JSON in your browser. Handles single-document and document-stream BSON. Output uses MongoDB's Extended JSON format so types like ObjectId, Date, and Decimal128 are preserved.

No uploadNo signupNo trackingFree, unlimited
Drop your BSON file here
or click to choose a file

How to use

  1. Drop your BSON file (or click to browse).
  2. The converter parses the file locally in your browser.
  3. JSON output is built in memory and offered for download.
  4. Click Download to save the JSON file.

FAQ

Does my data file upload to a server?

No. Conversion runs entirely in your browser using WebAssembly and Web APIs. Open the Network tab in DevTools while you convert — you'll see no outbound traffic carrying your file.

Is this really free?

Yes. No signup, no quota, no upgrade tier. The conversion runs on your machine, so it costs us nothing to host.

Is there a file size limit?

Browser memory is the only ceiling. On a modern desktop browser, a few hundred megabytes works fine. Mobile devices have tighter limits.

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