Is the TSV to JSON converter free?
Yes. It is completely free to use, with no signup, no account, and no paywall.
Do I need to install anything?
No. It runs in any modern browser on desktop or mobile, with nothing to download and nothing to configure.
Does it stay local?
Yes. Your data is converted entirely in your browser and never uploaded to a server.
Why are my numbers strings in the output?
Because guessing types is how data gets corrupted. A converter that helpfully turned 007 into 7 would break every product code and postcode in the file, and one that turned 1.10 into 1.1 would break version numbers. TSV carries no type information at all, so the honest thing to do is emit strings and let you cast the specific fields you know to be numeric. If you need typed output, do the conversion in code with an explicit schema.
Can a TSV value contain a tab character?
No, and this is the central limitation of the format. CSV solves the equivalent problem by wrapping a value in quotes, but TSV has no quoting or escaping convention, so a tab inside a value is indistinguishable from a column separator. Whatever produced your TSV either stripped those tabs or produced a file that no parser can read correctly. If your data contains tabs, use CSV or JSON as the interchange format.
Where do the JSON keys come from?
Straight from the first line, split on tabs, with no cleaning. A header cell containing a space produces a key containing a space, which is valid JSON but means you have to use bracket notation rather than dot notation to read it. If two header cells have the same text, the second column silently overwrites the first in every record, so it is worth glancing at the header row before you rely on the output.
What happens to short rows?
Missing trailing cells become empty strings, not null and not absent keys. Every object in the output therefore has the same set of keys as the header row, which keeps the result rectangular and easy to load into a table or map to a struct. It does mean you cannot distinguish a genuinely empty cell from a row that was cut short.
Is my data uploaded?
No. The TSV is split and rebuilt as JSON by JavaScript running in your browser. Data pasted out of a spreadsheet is usually real, so nothing is transmitted, logged, or stored.