generate a regex from examples by highlighting them

Paint the parts of your sample text you want to match and get a regular expression back - one that is verified to reproduce exactly your highlights before it is ever shown to you. No regex syntax required to start; real regex out.

how to use it

Paste a few lines of your real text - a log excerpt, a column of ids, whatever you are trying to match.
Highlight two or three examples of the part you want. Two beats one: the generalizer only widens as far as your examples justify.
Set match to say how literally to read the paint: this text for a constant, same shape for capitals-then-digits in the order painted, or any letters/numbers for any run of the same kinds of character, any length and any case.
Read the pattern. It is shown only after it has been tested to reproduce your highlights exactly.
Copy it, or use it in the workbench's extract with regex step to pull it into a new column.

Two or three paints beat one: the generalizer widens only as far as your examples justify.
Candidates climb a ladder - literals, character classes, boundaries - and every rung is tested.
match picks which rung to ask for. Painting the same word twice otherwise reads as a constant, which is right for status= and wrong for a city name; any letters/numbers says you meant the kind of thing, not the thing.
Splitting a delimited column is a job for the workbench's split at delimiter step, not a regex - click the column header there.
Copy the pattern, or use it directly in the workbench's extract-with-regex step.
Works on logs, IDs, dates, prices - anything with visible structure.

every tool in the box

data workbench - profile, clean, transform, and export CSV, JSON, and SQLite - the full suite
JSON flattener - nested JSON or NDJSON to flat columns, arrays and objects unrolled
CSV PII scrubber - find emails, phones, SSNs, and card numbers - mask, hash, or drop them
JSON to CSV - convert JSON or NDJSON to CSV with full column control
CSV to JSON - convert CSV to JSON or NDJSON, streamed at any size
Excel to CSV - read .xlsx workbooks and export CSV, sheets and all
CSV to Excel - write a real .xlsx where leading zeros and dates survive
SQL on CSV - real SQL over your files: joins, GROUP BY, a read-only console
CSV to SQLite - drop several files, get one .sqlite database with discovered foreign keys
CSV to SQL - CREATE TABLE and INSERT statements for Postgres, MySQL, SQL Server, SQLite
JSON to TypeScript - TypeScript interfaces and JSON Schema derived from your real data
large CSV viewer - open files past Excel's 1,048,576-row limit without loading them into RAM
regex painter - highlight example matches, get a verified regular expression back (this page)
log parser - read log files as events: layouts detected, stack traces kept whole, timestamps normalized, and a volume-over-time strip drawn in SQL across every row
visualize - chart any table you have open - bar, line, area or point - drag across it to filter, and export svg, png, or the vega-lite spec that drew it
theme builder - design, test, and export custom color themes with live previews, palette derivation, and contrast diagnostics

Like every unfckr tool, this runs 100% in your browser: no upload, no servers, no signup, no analytics. A Content-Security-Policy header blocks every programmatic network channel, so not even malicious code could phone home - and you can watch it happen: the privacy page runs six live escape attempts and shows the browser refusing each one.

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