Extract Text Between Brackets

Extract the text between square brackets on one line, including empty brackets.

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Regular expression
Reference

Regex quick reference

^ · $
Start/end; m = lines.
[abc] · \d
Listed character / digit.
* · + · ?
Zero or more, one or more, optional.
(...)
Capture a numbered group.
(?<name>...)
Named capture.
(?=...)
Ahead; lookbehind varies.
i · m · s
Ignore case / line anchors / dot-newline.
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Verified Fixture FX-R04

What it does

Extract the text between square brackets on one line; group 1 is the content, and empty brackets match too.

How to use it

  1. Load the example or paste your text.
  2. Check the matches and the unclosed-bracket counterexample.
  3. Export group 1.

Verified example

Example

Text "tag [alpha] and []"

JavaScript · This browser
\[([^\]\r\n]*)\]

Result: "[alpha]", "[]"

Python re · Local WASM
\[([^\]\r\n]*)\]

Result: "[alpha]", "[]"

PCRE2-8 · Local WASM
\[([^\]\r\n]*)\]

Result: "[alpha]", "[]"

Go regexp · Local WASM
\[([^\]\r\n]*)\]

Result: "[alpha]", "[]"

Counterexample

Text "[unclosed"

JavaScript · This browser
\[([^\]\r\n]*)\]

Result: no match

Python re · Local WASM
\[([^\]\r\n]*)\]

Result: no match

PCRE2-8 · Local WASM
\[([^\]\r\n]*)\]

Result: no match

Go regexp · Local WASM
\[([^\]\r\n]*)\]

Result: no match

Recorded by running fixture FX-R04 on : rp.js@1 on Node v24.21.0 (V8), v24.21.0, CPython 3.14.2 (Pyodide 314.0.7), PCRE2 10.48, go1.27.1. JavaScript results come from the rp.js@1 core on Node’s V8; your browser runs the same core.

Engines

Limits