Regular Expressions 101

1st Alternative(?<=\s)(\d+)\s(st(u?)k?)s?

Positive Lookbehind(?<=\s)

\sany whitespace character

Group 1(\d+)

\d+a digit, repeated at least once

\sany whitespace character

Group 2(st(u?)k?)

stthe literal text st (case sensitive)

Group 3(u?)

u?optionally matches the literal u (117₁₀ / 165₈ / 75₁₆) (case sensitive)

k?optionally matches the literal k (107₁₀ / 153₈ / 6B₁₆) (case sensitive)

s?optionally matches the literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

2nd Alternative(p((ie)?ce(s?)))

Group 4(p((ie)?ce(s?)))

pthe literal p (112₁₀ / 160₈ / 70₁₆) (case sensitive)

Group 5((ie)?ce(s?))

Group 6(ie)?

?repeats the group contents below at most once:

iethe literal text ie (case sensitive)

cethe literal text ce (case sensitive)

Group 7(s?)

s?optionally matches the literal s (115₁₀ / 163₈ / 73₁₆) (case sensitive)

Global pattern flags

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

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?<=\s)(\d+)\s(st(u?)k?)s?|(p((ie)?ce(s?)))

apple 10m
10mm
11ml
11kg
12g
13gr
14m3
15m2

apple 10 stuks 
10 pieces
11 pces
11 pce
12 stk
13 stuks
14m3
15m2