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The first line supplies the object keys, so every row after it maps onto those names. Empty header cells become awkward keys, and leading or trailing spaces are trimmed from each value before it is written into the JSON.
This is a straight comma split, not an RFC 4180 parser. Commas inside quoted fields, embedded newlines, and escaped quotes are not handled the way Excel or a dedicated library would. For those, clean the export or parse it in your own code.
The spreadsheet is read and converted in this browser tab and never sent to a server, so customer lists or internal exports do not leave your machine. Close the tab and nothing is retained.
That is the promise behind every tool here. Files are read in your browser tab, processed there, and discarded when you close it — never uploaded to our servers.
Flatten an array of objects to CSV.
Format, validate, prettify and beautify your JSON data instantly.
Format and parse YAML.
Test, visualize, and debug Regular Expressions instantly in your browser.
Encode to Base64 or decode from Base64 instantly in your browser.
Encode or decode query strings with encodeURIComponent — in your browser, nothing uploaded.
