Regular Expressions 101

Explanation
Pro

(?i)applies the following effective flags to the remainder of the pattern: gmi

i modifier: insensitive. Matches without distinguishing uppercase and lowercase letters

taxthe literal text tax (case insensitive)

Group 1(.*?)

.*?any character (except for line terminators), repeated any number of times

\s+any whitespace character, repeated at least once

Group 2([\d.]+)

Character Class[\d.]+

+matches at least one character from the set below:

\da digit

.the literal . (46₁₀ / 56₈ / 2E₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

(?i)tax(.*?)\s+([\d.]+)

New

TAX ID NO. 01.000.589.0.055.000
TAX ID. 01.000.589.0.055.000
TAX ID : 01.000.589.0.055.000
TAX ID 01.000.589.0.055.000
TAX: 01.000.589.0.055.000