What Symbols/Characters are Valid in a Domain Name?

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Your domain name is everyone’s way of remembering and finding your website. Your domain name refers to the name of your website and internet users can use your domain name instead of the web address (or IP address – a string of numbers) to access your website. A domain name could be any combination of letters and numbers and attached to domain name extensions, such as .com, .net, .org, and more. But, there are some rules around the characters and/or symbols that can be used in a domain name.

What characters or symbols are valid to use in a domain name? A valid domain name character would be derived from a set of alphanumeric ASCII characters, such as letters (a-z, A-Z), numbers (0-9), and dashes (-) or a combination all of these. A domain name can be any combination of such letters and numbers with up to 63 characters – 67 if you count the domain extension (.com, .net, .org, and others). The hyphen (-) is the only symbol that can be included in a valid domain name. There are no spaces in a domain name, nor is the use of the underscore ( _ ) allowed. Other common symbols such as exclamation points (!) and asterisks (*) are likewise not allowed.

Anyone who has been using the internet for a long time has likely encountered the acronym ASCII. This acronym is short for American Standard Code for Information Interchange and this is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other digital devices.

There is a lot of technical jargon in order to explain what ASCII is and how it is used in internet language. We will not be discussing that here at this time. What’s important for everyone to know is that, essentially, ASCII prescribes the characters or symbols that are valid for use in a domain name.

This information, while seemingly trivial, is a crucial element in everyone’s quest for the perfect domain name. Read on for a further understanding of characters and/or symbols that make a domain name valid.

Defining the 3 Types of Characters Allowed in a Domain Name: Letter, Number, and Special Characters

Valid characters that can be used in a domain name are A-Z (both upper-case and lower-case allowed), the numerical digits 0-9, and the hyphen (-).

  • Numbers: all ten Arabic numerals from 0 to 9.
  • Letters: this is divided into two blocks: upper-case and lower-case.
  • Symbols: only the hyphen or dash (-) can be included in a valid domain name.

How Many Characters Are Allowed in a Domain Name?

Domain names can be divided into two parts – Label and TLD. Let’s take amazon.com as an example. The label is amazon, while the TLD is .com. Top-level domains or domain extensions are the strings of text that come right after the label. A valid domain name has a minimum of 3 characters and can be up to 67 characters long — including the 4 characters used to identify the Top Level Domain (.com, .net, or .org, etc.). Remember to NOT type the “www.” before your domain name (label) when registering.

Can a Domain Name Have an Underscore?

Historically, search engines are not able to parse (analyze) punctuation marks. From an SEO standpoint, it is fortunate that Google has the ability to parse the underscore and the dash, along with a couple of other punctuation marks. But from a wider perspective, this is not the case.

Often, when writing in a format that does not allow spaces, people resort to the underscore ( _ ) to_write_something_with_spacing_that’s_human_readable. However, this is not necessarily how a computer will interpret the said symbol. Computers will typically use the hyphen (-) as a spacer, or-something-like-this. The underscore might be able to distinguish words for humans but could not differentiate them for computers. A_phrase_like_this will be parsed as Aphraselikethis.

As far as valid domain names go, there are no spaces in it, nor is the use of the underscore ( _ ) allowed.

Underscores are not allowed in domain names (labels) but are allowed in subfolders. Take this free online domain name generator tool, for example, www.naminggenerator.com/sub_folder/. The underscore in the URL (that is, anything that comes AFTER the .com) will work just fine.

Naming Generator Domain Search Image

Can a Domain Name Include a Hyphen or Dash?

A valid domain name uses the English character set and may contain letters (a-z and A-Z), numbers (0-9) and hyphens (-), or a combination of these three sets. However, there are particular guidelines to the use of the dash (or hyphen) in a valid domain name. A valid domain name:

  • Cannot begin nor end with a hyphen (-).
  • Does not contain a dash in the third and fourth positions (e.g. www.uv- -yz.com).
  • Multiple hyphens can be used but two hyphens cannot be used together. (e.g. www.this-is-okay.com but www.this- -is- -a- -no- -no.com).

Hyphens are allowed in domain names themselves, yes, and as a matter of fact, hyphens are likewise allowed for use in subdomains and subfolders. www.Your-Domain-Name.com/sub-folder-1/ is, theoretically, a perfectly valid URL.

Can You Use the Ampersand Symbol in a Domain Name?

Again, characters that you can use in your domain name include letters, numbers and hyphens. Unfortunately, you won’t be allowed to use the ampersand (&) as a part of your domain name. For example, the following domain name will not be allowed:

Take a look: this author actually typed “bacon&eggs.com” on the search box. Even Google wouldn’t hear of it.

Can a domain name start with a number?

For a domain name to be valid, it needs to begin with a letter or a number and end with a letter or a number.  So to answer this question: yes, a domain name can start with a number.

But some might also ask a follow-up question about “should”. In a previous article, we touched on the aesthetics of domain names, particularly in offline media (such as letterheads, business cards, and marketing materials). A few online experts are of the opinion that it might be best to just stick to alpha-texts when coming up with a domain name. It’s hard to verbally communicate a domain name that has a number in it. When your website travels via word-of-mouth (a viable marketing channel, believe it or not) it might be hard to determine if the number (or numbers) are written out as words or are numeric in form.

Your domain name may very well be the bedrock of your website’s success. Domain names are considered as the “real estate” of the vast worldwide web. Everyone who wants a piece of it will want “prime property”. An ideal domain name is often short and always easy to remember. Not many website users create bookmarks and would just remember the names of their favorite websites. These types of users just type the domain names out whenever they want to visit them. With this said, use all the valid domain name characters and create a unique name for your website, which is easy to spell. So that users could easily type it out without mistakes or without landing on an entirely different page. Domain names should always be more than good that it leaves a lasting first impression. The first step to all of this is finding that smashing idea of a domain name – then finding out if it’s available to register. Luckily, you have resources like this FREE domain name generator tool to help you get started on building your dream website.
















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