Unfckr is a free data workbench built by JT at uncSoft. One promise drives the design: your data never leaves your machine. Everything - parsing, transforms, SQL, exports - runs in your browser, and the deployment ships a Content-Security-Policy that blocks programmatic network access outright.
The suite covers profiling, cleaning, PII scrubbing, JSON flattening, SQL over files, SQLite import and export, typed code generation, and a regex-by-example painter. Source and contact: github.com/uncSoft.
A few things it does that most browser CSV tools do not. It profiles every column from the whole file rather than a sample, and raises a watchlist of what will fight you: empty or constant columns, mostly-null columns, values that differ only by case, duplicate headers. It repairs mojibake (José back to José) with a per-cell check that proves the repair before applying it, so text that only looks broken is left alone. Your cleaning steps belong to the file, not the tab: reopen a file and its pipeline comes back, and a different file with identical columns is offered those steps rather than having them applied behind your back. Before you build a join, the relationship map measures it, so you can see whether it will quietly drop rows or multiply them. And CSV is written the way you need it read: any delimiter, LF or CRLF, and the byte-order mark Excel wants for UTF-8.
Two sample databases ship with the app so you can see what it does without finding a file first. chinook.sqlite is the Chinook sample database by Luis Rocha, used under the MIT licence and unmodified apart from dropping optional indexes to halve the download. Copyright (c) 2008-2024 Luis Rocha. messy.sqlite is ours, and deliberately imperfect: real databases that are legally free to redistribute tend to be immaculate, so a tool that measures data quality has nothing to point at. That one has orphan rows, a join that multiplies rows, and two columns that share a name and nothing else. Three small log samples in the test suite (real-nginx-kv.log, real-auditd.log, real-suricata.log) are unmodified excerpts from splunk/attack_data, copyright Splunk Inc., used under the Apache License 2.0.