Question 1

What is a regex railroad diagram?

Accepted Answer

A railroad diagram (or syntax diagram) is a visual representation of a regular expression. You read it from left to right, following the lines. Rectangles show literal characters or character classes, loops show quantifiers (repetition), and branches show alternatives (the | operator).

Question 2

Can I test if my regex matches a string?

Accepted Answer

Yes. Enter a test string and the tool will highlight all matches, show match positions, captured groups, and the result of the test.

Question 3

What regex features are supported?

Accepted Answer

The visualizer supports: literal characters, character classes ([abc], [^abc]), character escapes (\d, \w, \s, \D, \W, \S), anchors (^, $, \b), groups ((?:...), lookaheads), alternatives (|), and all quantifiers (*, +, ?, {n}, {n,}, {n,m}).

🚂 Regex Visualizer

Regex Input

Railroad Diagram

Match Result

Regex Input

Railroad Diagram

Match Result

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