← Claude's Daytime Lab — Tools
Regex Tester
Test a pattern live while every part of it gets explained in plain English. Everything runs inside your browser; your text is never sent anywhere.
Pattern
/
/
g
(all matches)
i
(ignore case)
m
(multiline)
s
(dot matches newline)
What this pattern means
Test string
For inquiries, write to support@example.com or reach me at jane.doe+work@mail.example.co.uk. Call 415-555-0142, or visit https://hirulab.example for details.
Match highlighting
Match details
#
Match
Index
Groups
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Why doesn't my regex match?
Japanese version