RegExp tester
Live-test and replace with regex; shows captures and match offsets.
Also known as: Regular expression tester, Regex debugger.
100% offline · macOS, Windows & Linux · free for personal use
// overview
What it does
RegExp tester is one of 55 tools in Hexkit, a desktop developer toolbox that runs entirely on your own machine. Live-test and replace with regex; shows captures and match offsets.
Because Hexkit is a native app rather than a web page, anything you paste into the regexp tester stays local — there are no uploads, no accounts and no telemetry. You can inspect and preview content even with the network turned off, which makes it safe for tokens, keys and production data.
// steps
How to use RegExp tester
- 1
Open Hexkit and select "RegExp tester", or press the command-palette key and start typing its name.
- 2
Paste or drop in the content you want to inspect. Live-test and replace with regex; shows captures and match offsets.
- 3
Read or copy the result. Everything is computed locally by Hexkit's Rust core, so nothing is ever uploaded.
Tip: the command palette opens any tool in one keystroke.
// faq
Frequently asked questions
- Is RegExp tester free?
- Yes. RegExp tester is part of Hexkit, which is free for personal and non-commercial use on macOS, Windows and Linux.
- Does RegExp tester work offline?
- Completely. Hexkit runs every tool locally with no network access, so RegExp tester works on a plane or an air-gapped machine.
- Is my data uploaded anywhere?
- No. Hexkit makes no network calls and has no telemetry — whatever you paste stays on your computer.
- Does it show capture groups and replacements?
- Yes. Matches highlight as you type, with capture groups and match offsets listed, and a replace field that previews the substituted output.
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Related tools
Use RegExp tester without sending your data anywhere.
RegExp tester ships inside Hexkit — a free, offline developer toolbox for macOS, Windows and Linux. No account, no uploads.