Do I need to include regex delimiters?

No — just enter the pattern itself. Don't include / / delimiters.

What do I need to enter?

Just Regex Pattern and Test String. Every field has a sensible default you can start from.

Is my data uploaded anywhere?

No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.

Does it work on a phone?

Yes. The layout adapts to small screens and needs no app or signup.

Is Free Regex Visualizer free?

Yes. Free Regex Visualizer on TheToolss is free to use with no signup required for the core workflow.

Regex Visualizer

Visualize and break down regular expression patterns with explanations.

100% free
Private in browser
No signup
No watermarks

Regex Pattern

Test String

Pattern Breakdown

42 tokens

[

a

-

z

A

-

Z

0

-

9

.

_

%

+

-

]

+

@

[

a

-

z

A

-

Z

0

-

9

.

-

]

+

\.

[

a

-

z

A

-

Z

]

{2,}

Matches

2 matches

"[email protected]"index: 14

"[email protected]"index: 35

🎨 Color Legend:

Quantifiers & special Character classes Shorthand classes Groups & alternation Anchors & boundaries Literal characters

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About Regex Visualizer

Regex Visualizer on TheToolss helps you understand complex regular expressions by breaking them into color-coded tokens with explanations. Paste any regex pattern, test it against strings, and see each part explained.

How to use Regex Visualizer

Enter your regex pattern (without delimiters).
Optionally enter a test string to see matches.
View the color-coded token breakdown.

Key features

Color-coded token breakdown of regex patterns
Live match testing against sample strings
Capture group extraction
Flag descriptions
Handles character classes, quantifiers, groups, and anchors

Frequently asked questions

Do I need to include regex delimiters?: No — just enter the pattern itself. Don't include / / delimiters.
What do I need to enter?: Just Regex Pattern and Test String. Every field has a sensible default you can start from.
Is my data uploaded anywhere?: No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.
Does it work on a phone?: Yes. The layout adapts to small screens and needs no app or signup.
Is Free Regex Visualizer free?: Yes. Free Regex Visualizer on TheToolss is free to use with no signup required for the core workflow.

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