Regular Expressions 101

^start of line

-?optionally matches the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 1(\d+\.?|\.\d+)

1st Alternative\d+\.?

\d+a Unicode decimal digit, repeated at least once

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

2nd Alternative\.\d+

\.the literal . (46₁₀ / 56₈ / 2E₁₆)

\d+a Unicode decimal digit, repeated at least once

\d?optionally matches a Unicode decimal digit

Group 2(e-?\d+)?

?repeats the group contents below at most once:

ethe literal e (101₁₀ / 145₈ / 65₁₆) (case sensitive)

-?optionally matches the literal - (45₁₀ / 55₈ / 2D₁₆)

\d+a Unicode decimal digit, repeated at least once

$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

^-?(\d+\.?|\.\d+)\d?(e-?\d+)?$

Test String
New

0
true

0.1
true

abc
false

1 a
false

2e10
true

-90e3
true

1e
false

e3
false

6e-1
true

99e2.5
false

53.5e93
true

--6
false

-+3
false

95a54e53
false

.
false

Regular Expression

Test StringNew

SubstitutionProcessing...

Test String
New

Substitution
Processing...