Instant Regular Expression Tester
Test and debug Regex patterns against custom text strings in real-time.
STEP 1
Write your Regex pattern and select flags (g, i, m).
STEP 2
Paste your test string into the target field.
STEP 3
View live highlighted matches and output arrays.
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TEST STRING
MATCH RESULTS
0 matches
Results will highlight here...
Ready
Why Use JustRegex?
Testing complex Regular Expressions blindly in application code can lead to infinite loops or missed string validations. JustRegex evaluates patterns instantly using the native JavaScript `RegExp` engine inside your browser, providing visual match highlighting without sending sensitive string data to a server.