A regex generator helps you build and test regular expression patterns without memorizing syntax. Use the visual pattern builder for step-by-step construction, or use common presets to get started instantly.
Pattern
Test Strings (one per line)
Pattern Explanation
How to Use the Regex Generator
A regex generator (regular expression generator) helps you build text matching patterns without memorizing cryptic syntax. Whether you need to validate an email, extract phone numbers, or find specific patterns in log files, this tool makes it visual and testable.
Method 1: Use a Preset
Click any preset button (Email, URL, Phone, Date, IP, Hex Color, Credit Card, SSN, ZIP) to instantly load a tested pattern for that format. The pattern loads into the editor and immediately tests against your test strings. Presets are a great starting point — modify them as needed for your specific format requirements.
Method 2: Build from Pattern Blocks
Click the colored pattern blocks to insert regex components. Blue blocks are character classes (\d for digits, \w for word chars, . for any char). Green blocks are quantifiers (+ for one or more, * for zero or more). Purple blocks are anchors. Orange blocks are groups and lookaheads. Each click appends to the pattern at the cursor position.
Method 3: Build from Examples
Switch to "Build from Examples" mode and enter strings that should match and strings that should not match. The tool analyzes your examples and generates a pattern. This works well for structured formats like emails, dates, and phone numbers. Refine the generated pattern manually in the pattern editor after generation.
Test and Export
Enter test strings in the test area — one per line. Green lines match the pattern, red lines do not. Toggle flags (g for global, i for case-insensitive, m for multiline) to adjust matching behavior. When ready, copy the pattern with "Copy Regex" or as a ready-to-use literal with "Copy /pattern/flags".
FAQ
Is the regex generator free?
Yes, completely free with no account or signup needed. Build, test, and export as many regular expression patterns as you need.
What's the difference between Build from Pattern and Build from Examples?
Build from Pattern lets you construct a regex by clicking components (character classes, quantifiers, anchors, groups). Build from Examples lets you input strings that should match and strings that should not — the tool generates a pattern that fits your examples.
What regex flags are supported?
Six flags: global (g), case-insensitive (i), multiline (m), dotAll (s), unicode (u), and sticky (y). Toggle each individually. The current flag combination is shown in the output.
Can I test my regex against multiple strings at once?
Yes. Enter one test string per line in the test area. Each line is highlighted green (match) or red (no match) in real time. Captured groups are shown for matching lines.
What common regex presets are available?
Nine presets: Email, URL, US Phone, Date (YYYY-MM-DD), IP Address, Hex Color, Credit Card (masked), SSN pattern, and ZIP Code. Clicking a preset loads it into the pattern field and tests it immediately.
How do I copy the regex pattern?
Use 'Copy Regex' for just the pattern, 'Copy with Flags' for the full /pattern/flags format, or 'Download .txt' to save it as a text file.
What does the regex explanation show?
The explanation panel parses your regex pattern and shows a human-readable description of each component — what each character class, quantifier, and group means in plain English.