I have a URL validator as below

(^|\s)((https?:\/\/)?[\w-]+(\.[\w-]+)+\.?(:\d+)?(\/\S*)?)

which seems to cover most bases, but one that it can't, which is to allow localhost url's

I want to allow

http://localhost:8080

or

localhost:8080

But I don't want to allow simple string like

http://google

or

google

I have a URL validator as below

(^|\s)((https?:\/\/)?[\w-]+(\.[\w-]+)+\.?(:\d+)?(\/\S*)?)

which seems to cover most bases, but one that it can't, which is to allow localhost url's

I want to allow

http://localhost:8080

or

localhost:8080

But I don't want to allow simple string like

http://google

or

google

• javascript
• regex
• url

2 Answers 2

You can use this regex to allow localhost as a valid hostname:

(?:^|\s)((https?:\/\/)?(?:localhost|[\w-]+(?:\.[\w-]+)+)(:\d+)?(\/\S*)?)

RegEx Demo

Also you can use this RegEx

^((https?:\/\/)?(([\w-]+(?:\.[\w-]+)+)(:\d{1,5})?|([\w-]+:\d{1,5}))(\/\S*)?)$

RegEx Demo