Regex Pattern Builder
Assemble a regular expression from building blocks and test it against your text as you go.
Your pattern
^ Start of text[A-Za-z0-9] Letter or digit+ 1 or more@ At sign @/^[A-Za-z0-9]+@/g
Position
Characters
Groups & logic
Repeat the previous block
Exact text
Any one of these characters
Test
1 match
jai@ example user42@ hello world 2026
Use it in code
const re = /^[A-Za-z0-9]+@/g; const matches = text.match(re);