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Regular expression for format xx-xx (does not contain letters)

I am trying to use regex to check if the user input is in the correct format xx-xx (input only accepts numbers, does not accept alphanumeric characters)
I tried: /[1-9]{1,}\-[1-9]{1,}/ but when entering alphabetic characters still pass this test.
Can you guys help me. Thank.

Your regex is just fine, you just need to add positional asserts, "^" for the start of the string and "$" for the end of the string:
/^[1-9]{2}\-[1-9]{2}$/
It is better to put "{2}" if you only want xx-xx

/\d{2}-\d{2}/
Worked for me.
Breakdown:
\d checks for a digit character, i.e. 0-9.
{2} checks for two digits next to each other specifically.
- just checks for the hyphen character.

On the other hand, you can have several cases depending on what you are looking for precisely.
In case you agree that an xx-xx value can be 00-00 and any other value, you should use this regex instead:
/^\d{2}-\d{2}$/
In case you accept that an xx-xx value is never 00-00 but can be 01-03 and any other value, but never 00-00, you should use this regex (a bit long, sorry, but does the job perfectly):
/^[1-9](?=[0-9])[0-9]-[1-9](?=[0-9])[0-9]$|^[0-9](?=[1-9])[1-9]-[0-9](?=[1-9])[1-9]$/
Enjoy !

need a regex for password validation that allows all special characters [duplicate]

This question already has an answer here:
Password validation (regex?)
(1 answer)
Closed 8 years ago.
The password requirements are:
at least two letters
at least two numbers
at least one special character (any special character)
at least 8 characters
This one is close but isn't working:
/^(?=.*\d)(?=.*[a-zA-Z])(?=.*[\W]).{8,}$/
What am I doing wrong?

This regex meets your requirements:
/^(?=(?:[^a-z]*[a-z]){2})(?=(?:[^0-9]*[0-9]){2})(?=.*[!-\/:-#\[-`{-~]).{8,}$/i
Play with the demo to see what matches and doesn't match.
Explanation
This is a classic password validation technique with lookarounds as explained in this article
The i flag at the end makes it case-insensitive so we don't have to say a-zA-Z
The ^ anchor asserts that we are at the beginning of the string
The first lookahead (?=(?:[^a-z]*[a-z]){2}) asserts that what follows at this position (the beginning of the string) is any characters that are not a letter, followed by one letter... twice, ensuring there are at least two letters
The second lookahead (?=(?:[^0-9]*[0-9]){2}) asserts that what follows at this position (still the beginning of the string) is any characters that are not a digit, followed by one digit... twice, ensuring there are at least two letters
The third lookahead (?=.*[!-\/:-#\[-{-~])` asserts that what follows at this position (still the beginning of the string) is any characters, followed by one special character
The $ anchor asserts that we are at the end of the string
Note about special characters
The regex [!-\/:-#\[-{-~]` specifically picks out all printable chars that are neither digits nor letters from the ASCII table. If this includes chars you don't want, make it more restrictive.

A regex is probably inappropriate for this; it's hard to glance at the regex you've got and immediately have any idea what the requirements are, let alone how to modify them. You might want to just count the number of characters in each group directly, then check that those counts all pass the appropriate threshold.
That said: consider that this would enforce really awkward passwords, yet disallow xkcd-style passwords. I strongly encourage you to take a more heuristic approach, where a longer password loosens the other restrictions. There are other considerations to enforcing a strong password, too, like similarity to dictionary words and number of unique characters.
Honestly you might be best off just requiring passphrases :)

I'd say:
/^(?=.*\d.*\d)(?=.*[a-zA-Z].*[a-zA-Z])(?=.*[\W]).{8,}$/
Your regex was missing the 2 digits and 2 letters requirements.

How about:
/^(?=.{2,}\d)(?=.{2,}[a-zA-Z])(?=.*[\W]).{8,}$/
It should meet your requirement.

Depends on what you consider to be a "special character". If a special character is anything that is not a digit or a letter, and if Spaces are not allowed in the password, then:
^(?=(?:\S*\d){2})(?=(?:\S*[A-Za-z]){2})(?=\S*[^A-Za-z0-9])\S{8,}
or, with the "escapes":
"^(?=(?:\\S*\\d){2})(?=(?:\\S*[A-Za-z]){2})(?=\\S*[^A-Za-z0-9])\\S{8,}"
If you choose to allow spaces, replace \S with a dot .
If you want to define "special characters" as only including certain characters, or as excluding other characters in addition to letters and digits, edit the character class in the final lookahead.

Identifying special non alphanumeric characters in a string

Im working on a password validation that should only allow a-z 0-9 and these characters "!"#$%&'()*+,-./:;<=>?#[\]^_{|}~`
I tried using a regex but I'm not too good with them and I wasnt sure if this is even possible or if Im not escaping the correct characters.
var allowedCharacters = /^[A-Za-Z0-9!"#$%&'()*+,-.\/:;<=>?#[\\]^_`{|}~]+$/;
if (!s.value.match(allowedCharacters)){
displayIllegalTextError();
return false;
}

You need to place the dash at the start or end of the regex, or it will try to create a character range (,-.). Then, a-Z isn't a valid range, you probably meant a-z. Also, you need to escape the closing brackets:
/^[A-Za-z0-9!"#$%&'()*+,.\/:;<=>?#[\\\]^_`{|}~-]+$/

Looking over the ascii chart here I see your regex could be reduced to this character range:
/^[\x21-\x7e]+$/
If you just want to learn special behavior of character classes, you should read up
on it via regex basic tutorials.
Note that class behavior differs amongst the different flavors.

Simpler and more to the point using unicode: ^[\u0021-\u007E]+$.
/^[\u0021-\u007E]+$/.test('MyPassword!') // returns true
/^[\u0021-\u007E]+$/.test('MyPassword™') // returns false
Now if you would like to go a few steps further and actually create a more complex validation such as: minimum length 8 characters and at least one lowercase, one uppercase, one digit and one special character:
^(?=.*[a-z])(?=.*[A-Z])(?=.*[0-9])(?=.*[^a-zA-Z0-9])[\u0021-\u007E]{8,}$

UK bank sort code javascript regular expression

I'm trying to create a regular expression in javascript for a UK bank sort code so that the user can input 6 digits, or 6 digits with a hyphen between pairs. For example "123456" or "12-34-56". Also not all of the digits can be 0.
So far I've got /(?!0{2}(-?0{2}){2})(\d{2}(-\d{2}){2})|(\d{6})/ and this jsFiddle to test.
This is my first regular expression so I'm not sure I'm doing it right. The test for 6 0-digits should fail and I thought the -? optional hyphen in the lookahead would cause it to treat it the same as 6 0-digits with hyphens, but it isn't.
I'd appreciate some help and any criticism if I'm doing it completely incorrectly!

Just to answer your question, you can validate user input with:
/^(?!(?:0{6}|00-00-00))(?:\d{6}|\d\d-\d\d-\d\d)$/.test(inputString)
It will strictly match only input in the form XX-XX-XX or XXXXXX where X are digits, and will exclude 00-00-00, 000000 along with any other cases (e.g. XX-XXXX or XXXX-XX).
However, in my opinion, as stated in other comments, I think it is still better if you force user to either always enter the hyphen, or none at all. Being extra strict when dealing with anything related to money saves (unknown) troubles later.

Since any of the digits can be zero, but not all at once, you should treat the one case where they are all zero as a single, special case.
You are checking for two digits (\d{2}), then an optional hyphen (-?), then another two digits (\d{2}) and another optional hyphen (-?), before another two digits (\d{2}).
Putting this together gives \d{2}-?\d{2}-?\d{2}, but you can simplify this further:
(\d{2}-?){2}\d{2}
You then use the following pseudocode to match the format but not 000000 or 00-00-00:
if (string.match("/(\d{2}-?){2}\d{2}/") && !string.match("/(00-?){2}00/"))
//then it's a valid code, you could also use (0{2}-?){2}0{2} to check zeros
You may wish to add the string anchors ^ (start) and $ (end) to check the entire string.

Need help: RegEx for a password containing numbers and special chars

I need help with a RegEx for a password. The password must contain at least one special char (like "§$&/!) AND a number.
E.g. a password like "EdfA433&" must be valid whereas "aASEas§ö" not as it contains not a number.
I have the following RegEx so far:
^(?=.*[0-9])(?=.*[a-zA-Z]).{3,}$
But this one is obviously checking only for a number. Can anyone help?

You're better off just using multiple more simple regular expressions: any code checking anything like this won't be performance sensitive, and the additional complexity of maintenance given a more complex regexp probably isn't justifiable.
So, what I'd go for:
var valid = foo.match(/[0-9]/) && foo.match(/["§$&/!]/);
I wonder if you really want to define special characters like that: Does é count as a special character? Does ~ count as a special character?

^(?=.*\d)(?=.*\W).{3,}$
checks for at least one digit (\d) and one non-alphanumeric character (\W). \W is the inverse of \w which matches digits, letters and the underscore.
If you want to include the underscore in the list of "special characters", use
^(?=.*\d)(?=.*[\W_]).{3,}$

I would divide function that checks if password is "hard" into some parts and in each part I would check one condition. You can see some complicated regex on Daily WTF with password reset: http://thedailywtf.com/Articles/The-Password-Reset-Facade.aspx