Regular Expressions 101

^start of line

Character Class[a-z0-9]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

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

Non-Capturing Group(?:-[a-z0-9]+)*

*repeats the group contents below any number of times:

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Character Class[a-z0-9]+

+matches at least one character from the set below:

a-zone character from a (97₁₀) to z (122₁₀) (case sensitive)

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

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

jpgthe literal text jpg (case sensitive)

$end of line

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.

Search reference

Regular Expression

^[a-z0-9]+(?:-[a-z0-9]+)*\.jpg$

New

test-file.jpg
test-123-test.jpg
123-456-thumbnail.jpg
test--123----.jpg