regex101: ISO 8601 Duration Validator

Explanation

Pro

^start of string

Pthe literal P (80₁₀ / 120₈ / 50₁₆) (case sensitive)

Group 1(([0-9]+Y)?([0-9]+M)?([0-9]+W)?([0-9]+D)?(T([0-9]+H)?([0-9]+M)?([0-9]+(\.?[0-9]+)?S)?))?

?repeats the group contents below at most once:

Group 2([0-9]+Y)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Ythe literal Y (89₁₀ / 131₈ / 59₁₆) (case sensitive)

Group 3([0-9]+M)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Mthe literal M (77₁₀ / 115₈ / 4D₁₆) (case sensitive)

Group 4([0-9]+W)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Wthe literal W (87₁₀ / 127₈ / 57₁₆) (case sensitive)

Group 5([0-9]+D)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Dthe literal D (68₁₀ / 104₈ / 44₁₆) (case sensitive)

Group 6(T([0-9]+H)?([0-9]+M)?([0-9]+(\.?[0-9]+)?S)?)

Tthe literal T (84₁₀ / 124₈ / 54₁₆) (case sensitive)

Group 7([0-9]+H)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Hthe literal H (72₁₀ / 110₈ / 48₁₆) (case sensitive)

Group 8([0-9]+M)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Mthe literal M (77₁₀ / 115₈ / 4D₁₆) (case sensitive)

Group 9([0-9]+(\.?[0-9]+)?S)?

?repeats the group contents below at most once:

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Group 10(\.?[0-9]+)?

?repeats the group contents below at most once:

\.?optionally matches the literal . (46₁₀ / 56₈ / 2E₁₆)

Character Class[0-9]+

+matches at least one character from the set below:

0-9one character from 0 (48₁₀) to 9 (57₁₀)

Sthe literal S (83₁₀ / 123₈ / 53₁₆) (case sensitive)

$end of string

Quick Reference

26 tokens

Regular Expression

^P(([0-9]+Y)?([0-9]+M)?([0-9]+W)?([0-9]+D)?(T([0-9]+H)?([0-9]+M)?([0-9]+(\.?[0-9]+)?S)?))?$

^P(([0-9]+Y)?([0-9]+M)?([0-9]+W)?([0-9]+D)?)?(T(([0-9]+)H)?(([0-9]+)M)?(([0-9]+\.?[0-9]*)S)?)?$

Substitution

^P(([0-9]+Y)?([0-9]+M)?([0-9]+W)?([0-9]+D)?)?(T(([0-9]+)H)?(([0-9]+)M)?(([0-9]+\.?[0-9]*)S)?)?$