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String Length Calculator

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Use this free online String Length Calculator which counts the length of the string instantly. Either you can copy and paste your text in the text area above, or you can type your text. By clicking the Submit button the counter will display the number of characters and whitespace in your text.

What are String Functions?

In computer programming languages, string functions are used to manipulate a string or query information about a string. A basic example of a string function is the length (string) function. For example, length("hello world") would return 11.

String length function returns the length of a string literal. A string literal is a sequence of characters surrounded by double quotation marks (").

Most programming languages that have a string datatype will have some string functions. There may be other low-level ways within each language that handle strings directly. In object-oriented languages, string functions are often implemented as properties and methods of string objects. In functional and list-based languages a string is represented as a list, therefore all list-manipulation procedures could be considered string functions. However such languages may also implement a subset of explicit string-specific functions.

Modern object-oriented languages, like C# and Java, have immutable strings and return a copy (in newly allocated dynamic memory) for a function that manipulates strings, while others, like C manipulates the original string unless the programmer copies data to a new string.

What is a String?

In programming, a string is any finite sequence of characters (i.e., letters, numerals, symbols, and punctuation marks).

A string is a contiguous sequence of symbols or values, such as a character string (a sequence of characters) or a binary digit string (a sequence of binary values). It is used to represent text rather than numbers. It consists of a set of characters that can also contain spaces and numbers.

A string is considered as a data type and is often implemented as an array data structure of bytes or words that stores a sequence of elements, typically characters, using some character encoding. A string may also denote more general arrays or other sequences (or list) data types and structures.

It is known as a string literal or an anonymous string when a string appears in source code.

A string is a finite sequence of symbols that are chosen from a set called an alphabet in formal languages.

Formal strings can have an arbitrary but finite length, but the length of strings in real languages is often constrained to an artificial maximum. There are two types of string datatypes: fixed-length strings and variable-length strings. Fixed-length strings have a fixed maximum length to be determined at compile-time and use the same amount of memory whether this maximum is needed or not. The length of variable-length strings is not arbitrarily fixed and can use varying amounts of memory depending on the actual requirements at run time. In modern programming languages, most strings are variable-length strings. Even variable-length strings are limited in length by the number of bits available to a pointer, and by the size of available computer memory. The string length can be stored as a separate integer, which may put an artificial limit on the length, or implicitly through a termination character, usually a character value with all bits zero such as in C programming language.

A string datatype is a datatype modeled on the idea of a formal string. Data types differ according to the programming language or database system, but strings are such an important and useful datatype that they are implemented in nearly every programming language. In some languages, strings are available as primitive types and in others as composite types. The syntax of most high-level programming languages allows for a string, usually quoted in some way, to represent an instance of a string datatype; such a meta-string is called a literal or string literal. For example, some languages like C++ implement strings as templates that can be used with any datatype.

Some languages, such as C++ and Ruby, normally allow the contents of a string to be changed after it has been created. These are called mutable strings. In languages such as Java and Python, the value is fixed and a new string must be created if any alteration should be made. These are called immutable strings.

Security Concerns

The differing memory layout and storage requirements of strings can affect the security of the program accessing the string data. String data is frequently obtained from user input to a program. It is the responsibility of the program to validate the string to ensure that it represents the expected format. Performing limited or no validation of user input can cause a program to be vulnerable to code injection attacks.