Writing a regular expression by hand is fiddly and error-prone. The GigAI Regex Generator flips it around: paste a few examples of the strings you want to match (order codes, dates, IDs, emails) and it infers a pattern for you.
Writing a regular expression by hand is fiddly and error-prone. The GigAI Regex Generator flips it around: paste a few examples of the strings you want to match (order codes, dates, IDs, emails) and it infers a pattern for you. It first checks whether your examples are a known format (email, URL, IPv4, ISO date, time, UUID, hex color, integer, decimal) and emits a clean, battle-tested regex for it. Otherwise it analyzes the structure of your examples, splitting each into runs of digits, letters, spaces and separators, and generalises them into character classes and quantifiers, so 'ORD-2024-001' and 'ORD-2023-118' become [A-Z]{3}-\d{4}-\d{3}. You can also paste strings that should NOT match to tighten the result, and every pattern is validated against your examples so you can see honestly whether it works. It's a heuristic, not magic: highly varied inputs get a broad pattern you can refine. Everything runs in your browser, your data never leaves the page.
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One example per line: order codes, dates, IDs, emails, anything. A few varied examples work best.
Provide counter-examples to tighten the pattern. The tool checks the regex rejects them.
Read the plain-English explanation, confirm the validation is green, and copy the pattern into your code.
For complex inputs you'll get a broad starting pattern, tweak it by hand, or add more consistent examples.
If your examples are emails, URLs, IPs, dates, UUIDs, hex colors or numbers, it emits a clean, hand-tuned regex for that format.
For custom strings it analyzes the pattern of digits, letters and separators and generalises it: 'AB-123' becomes [A-Z]{2}-\d{3}.
Every result is tested against your examples. Add strings that should NOT match to tighten it. The tool shows whether it passes.
A plain-English breakdown says exactly what the pattern matches, so you can trust it and tweak it with confidence.
Describe what you want by example instead of memorising syntax. Perfect when you know the strings but not the pattern language.
Skip the write-test-tweak loop. Paste examples, get a validated pattern, and refine from a working starting point.
Your example data (which might be real records) is analyzed locally in your browser and never uploaded.
Build and debug regular expressions with live match highlighting. Toggle the g/i/m/s/u/y flags, watch every match light up in your test string, inspect numbered and named capture groups, preview a find-and-replace, and drop in ready-made patterns from a built-in library. 100% in-browser. Nothing is uploaded.
Compare two texts side by side and highlight every added, removed and changed line, word or character, with unified or split view, ignore-whitespace and ignore-case, all in your browser.
Validate JSON against RFC 8259 with the exact error line, column and a caret under the bad character. Get plain-English explanations, one-click auto-fix for trailing commas and single quotes, plus depth, key-count and type stats, nothing uploaded.
Paste any URL and instantly break it into protocol, host, port, path, every query parameter, hash and origin, with a live rebuilt URL to confirm the parts. 100% in your browser.
Generate scannable 1D barcodes (CODE128, EAN-13, UPC-A, CODE39, ITF-14, MSI, pharmacode and Codabar) live in your browser, with per-format validation and PNG or SVG export. Nothing is uploaded.
Decode Base64 back to text or a file instantly: Unicode-safe, auto-detects URL-safe input, sniffs binary data and offers a download. Runs fully in your browser, nothing uploaded.
Everything runs 100% in your browser. Your files are never uploaded to a server, never stored, and never seen by anyone but you.
Free, private and instant. Regex Generator runs right in your browser.
