Free Online Regulex Visualizer (Regular Expression Diagrammer)

Build, test, and visualize regular expressions with live pattern matching and explanations.

How to use Regulex Visualizer

Enter your regular expression pattern
Type or paste test text to match against
Enable regex flags as needed (g, i, m, s)
View matches highlighted in your test text
See visual pattern breakdown and explanation

Keyboard Shortcuts

Ctrl+Enter Test Regex

Ctrl+Z Undo

Ctrl+Shift+Z Redo

Common Patterns

Regular Expression Pattern

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Global (g) Case Insensitive (i) Multiline (m) Dot All (s)

chars

matches

Valid Pattern Invalid Pattern

Test String

Matches Found:

Pattern Structure

Pattern Explanation

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How to Use

Step-by-step guide 3 steps

1 Input Regular Expression: Paste or type your Regex pattern into the input field.
2 Generate Diagram: The tool instantly converts the complex pattern into an intuitive visual railway diagram.
3 Analyze Flow: Follow the lines of the diagram to understand exactly which characters, loops, and conditions the regex engine will match. Visualize Regex now!

FAQ

Common questions 3 questions

What does the railway diagram represent?

It graphically represents the state machine of the regular expression, showing all possible paths a string can take to be considered a match.

Is it compatible with all regex flavors?

It typically supports common flavors like PCRE, JavaScript, and Python regex, but minor syntax differences may apply.

Why is regex hard to read?

The nested syntax and special characters make it highly condensed; the Regulex Visualizer breaks this down visually.

Use Cases & Examples

Real-world applications 3 examples

Debugging

Instantly identify logical flaws or unintended capturing groups in a long or complex regular expression.

Learning

Use the visual output to easily understand how quantifiers (+, *) and lookaheads work.

Documentation

Include the clear, visual railway diagram in technical documentation instead of the raw, cryptic regex string.