MatchesGroupsFlags
Common Patterns
Test patterns without second-guessing what matched.
Paste a regex, set flags, and inspect every match with positional and named capture groups. The scanner lists all matches even if you forget the g flag.
Input
Regex setup
/ /gi
Validation
Pattern status
Pattern matched the input
Review the preview and capture groups below to inspect each occurrence.
60 Pattern chars
2 Flag chars
102 Input chars
2 Listed matches
g
Global: match all occurrences.
i
Ignore case: case-insensitive.
m
Multiline: anchors ^ and $.
s
DotAll: . matches newlines.
Preview
Highlighted text
Primary link: https://usefulonlinetools.app/regex-checker
Backup link: http://localhost:5173/dev-tools
Matches
Occurrence breakdown
Match 1 Index 14 · Len 43
https://usefulonlinetools.app/regex-checker$1
https$2
usefulonlinetools.app$3
/regex-checkerprotocol
httpshost
usefulonlinetools.apppath
/regex-checkerMatch 2 Index 71 · Len 16
http://localhost$1
http$2
localhost$3
(undefined)protocol
httphost
localhostpath
(undefined)Other Live Tools
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