[majkinetor]

Tools do exist actually

- Tad does this for CSV, and much more, like pivots

- XLS can be natively queried with SQL with many tools, for example dbeaver

- I am not aware of JSON tool, but this is trivially achievable with postgresql by just adding json as only field in the table and then using SQL to query it, even index it.

No single tool tho, but you can easily automate any of the above via script and have it locally, without browser which is instant show stopper for any serious work.

[chanar]

Thanks! Still, no simple solution to do it quickly. Using additional tools needs some sort of technical knowledge.

[majkinetor]

Sort of.

On Windows:

    choco install tad dbeaver postgresql

Tad and dbeaver usable ASAP. PostgreSql requires creating empty database and single table once, with json type column, then insert json each time.

On the more positive side, you have infinitely more capable features in those tools and standard SQL

However, for quick and dirty and ad hoc place, web tool looks like a way to go.

[seektable]

For CSV/TSV files SeekTable can do various reporting (including pivots) really quickly, naturally just in a few clicks.