Aan de slag
Create your account and run your first regular expression in under five minutes.
RegexNest gives you a live, interactive playground where you can write, test, and debug regular expressions against real text — no setup, no installs. This guide walks you through signing up, configuring your workspace, and running your first pattern from scratch.
Whether you are parsing log files, validating user input, or extracting data from HTML, the workflow is the same: type a pattern, supply test strings, and read the colour-coded match breakdown in real time.
Create your account
1. Open the sign-up page
Navigate to app.regexnest.com/signup. You can register with a Google account, a GitHub account, or a standard email address. All three options give you full access to the playground — the only difference is convenience.
2. Verify your email
If you signed up with email, check your inbox for a verification message from no-reply@regexnest.com. Click the link inside to activate your account. The link expires after 24 hours; if it expires, request a new one from the sign-in page.
3. Choose a workspace name
After verification you land on the workspace dashboard. You start with one default workspace called "My Patterns". You can rename it, create additional workspaces (e.g., "Client Projects", "Learn Regex"), or delete it — each workspace holds its own set of saved patterns and test files.
Run your first regex
Once your account is ready, click the "+ New Pattern" button in your workspace. The editor opens with three panes: the pattern input on top, the flags bar beneath it, and the test-string area below that.
Enter a pattern
Type the following into the pattern field to match email addresses:
^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$
As you type, the editor highlights syntax errors in red and shows a live token breakdown along the right edge.
Set your flags
Flags modify how the engine interprets your pattern. For this email example, leave all flags unchecked (the default). Later you might enable g (global) to find every match in a string, or i (case-insensitive) to ignore letter casing.
Add test strings
Paste one or more lines into the test area and watch the results update instantly. Try these three examples:
• maria.vos@example.nl — matches
• john.doe@company.co.uk — matches
• invalid-email@ — no match
Matched text is highlighted in green; unmatched lines stay grey. Click any highlighted segment to see the captured groups.
When you are happy with the result, hit Ctrl + S (or click the save icon) to store the pattern in your workspace. You can share it via a public link, export it as JSON, or duplicate it to iterate on a variation.