Online Random String Generator

The most simple online utility that generates random strings. Free, quick and powerful Random String Generator that allows you to flexibly create random strings ranging from minimum 8 to maximum 25 character length.

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String length


What is a Random String Generator?

Random String Generator generates random strings of one or more characters in length. You can customize the string's length, from a minimum of 8-character length to a maximum of 25-character length. This module is designed to generate pseudo-random numbers or sequences, and it can prove useful for generating non-security-related strings.

How do you Generate Random Strings?

Here's a step-by-step guide on how to generate random strings using the LambdaTest Random String Generator:

  • Choose String Length: On the tool's interface, you'll find a dropdown labeled "String length". This dropdown allows you to select the desired length of the random string you want to generate. The tool provides options ranging from a minimum of 8 characters to a maximum of 25 characters.
  • Generate the String: Once you've selected the desired string length, simply click on the "Generate" button. The tool will then produce a random string of the specified length.
  • View the Output: The generated random string will be displayed in the "Output" section below the "Generate" button. You can copy this string and use it as needed.

How to generate a set of random strings?

To generate multiple random strings:

  • Follow the steps mentioned above.
  • You can copy the string and save it somewhere.
  • You can repeat the process “n” number of times until you have received the desired number of strings.

How does Random String Generator work?

A Random String Generator works by utilizing algorithms and specific character sets to produce a sequence of characters randomly. Here's a detailed breakdown of how it operates.

Character Set Selection:

Before generating a random string, the tool needs a set of characters to choose from. This set can include:

  • Uppercase letters (A-Z)
  • Lowercase letters (a-z)
  • Numbers (0-9)
  • Special characters (e.g., @, #, $, %, &, *)

Determine String Length:

The user specifies the desired length of the random string. This determines how many characters the final string will contain.

Randomization Algorithm:

The core of the tool is the randomization algorithm. This algorithm selects characters from the chosen set at random. There are various algorithms to achieve this, such as:

  • Pseudo-Random Number Generators (PRNGs): These are algorithms that use mathematical formulas to produce sequences of random numbers. They start from an initial number called a 'seed'. Given the same seed, they will produce the same sequence of numbers, hence the term "pseudo-random".
  • True Random Number Generators (TRNGs): These rely on genuinely random physical processes, like electronic noise, to generate numbers. They don't require a seed and are considered more random than PRNGs.

Character Selection:

For each position in the string, the algorithm picks a character at random from the character set. It does this by generating a random number corresponding to an index in the character set. The character at that index is then added to the string.

Repeat Until Desired Length:

The tool repeats the character selection process until the string reaches the user-specified length.


Once the string reaches the desired length, the tool outputs the generated string to the user. In essence, a Random String Generator combines user preferences (like string length and character set) with a randomization algorithm to produce a unique sequence of characters. This ensures that each generated string is unpredictable and different from the previous ones, making it ideal for various applications like password generation, unique ID creation, and more.

How do you Randomize 3 strings in Python?

In Python, you can randomise a list of strings using the random.shuffle() method from the random module, and you can randomise a specific number of elements from a list using random.sample().

import random
strings = ['string1', 'string2', 'string3']


import random
strings = ['string1', 'string2', 'string3']
randomized_strings = random.sample(strings, 3)

Both methods will return the three strings in a randomised order.

What is Random String in Python?

A random string in Python is a sequence of characters generated by a random number generator or a random character generator. These strings can be generated using built-in libraries like random and string, as well as external libraries designed specifically for generating random strings.

What can you do with Random String Generator?

A Random String Generator is a versatile tool that produces a sequence of characters randomly. This tool can be used for various purposes, from generating unique IDs and passwords to creating test data for software applications. With the ability to customize the length and character set, users can tailor the output to fit specific requirements.

Applications of a random string generator

  • Password Generation: Create strong, unique passwords for online accounts.
  • Unique ID Creation: Generate unique IDs for database entries.
  • Testing & Development: Produce random test data for software and applications.
  • URL Shorteners: Generate short, unique URLs.
  • Cryptography: Create random keys for encryption.

Generate Random Unbounded String With Plain Java

Using Java, you can generate an unbounded random string:

import java.util.UUID;

public class RandomString {
    public static void main(String[] args) {
        String randomString = UUID.randomUUID().toString();

This method uses the UUID class to generate a random string.

Generate Random Bounded String With Plain Java

For a bounded string of a specific length:

import java.util.Random;

public class RandomString {
    public static void main(String[] args) {
        int length = 10;
        String characters = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
        Random random = new Random();
        StringBuilder randomString = new StringBuilder();

        for (int i = 0; i < length; i++) {
            int index = random.nextInt(characters.length());


Generate Random Alphabetic String With Java 8

Java 8 introduced streams, which can be used to generate random strings:

import java.util.Random;

public class RandomString {
    public static void main(String[] args) {
        int length = 10;
        Random random = new Random();
        String randomString = random.ints(65, 91)
                .mapToObj(i -> (char) i)


Generate Bounded Random String With Apache Commons Lang

Using the Apache Commons Lang library:

import org.apache.commons.lang3.RandomStringUtils;

public class RandomString {
    public static void main(String[] args) {
        int length = 10;
        boolean useLetters = true;
        boolean useNumbers = false;
        String randomString = RandomStringUtils.random(length, useLetters, useNumbers);


Generate Alphabetic String With Apache Commons Lang

For alphabetic strings:

String randomString = RandomStringUtils.randomAlphabetic(length);

Generate Alphanumeric String With Apache Commons Lang

For alphanumeric strings:

String randomString = RandomStringUtils.randomAlphanumeric(length);

Frequently Asked Questions (FAQs)

What is the LambdaTest Random String Generator?

The LambdaTest Random String Generator is a free online tool that allows users to generate random strings of varying lengths. It's useful for various purposes, including testing, password generation, and more.

How many characters can I generate using this tool?

You can generate random strings ranging from 8 to 25 characters in length using the LambdaTest Random String Generator.

Is there a limit to how many strings I can generate?

No, there's no limit. You can generate as many random strings as you need.

Can I specify the type of characters used in the random string?

Currently, the tool generates alphanumeric strings. It doesn't allow for specific character type selection, but the generated strings are a mix of both numbers and letters.

Is the generated string truly random?

Yes, the strings generated by the tool are random and unique for each generation.

Can I use the generated strings for password generation?

Yes, the random strings generated can be used as passwords. However, always ensure that the generated string meets the security criteria required for your specific use case.

Is it safe to use this tool? Does LambdaTest store the generated strings?

The tool is safe to use. LambdaTest does not store or log any of the random strings generated by users.

Do I need to sign up or log in to use the Random String Generator?

No, the tool is freely accessible to all users without the need for registration or login.

Can I use this tool offline?

No, the LambdaTest Random String Generator is an online tool and requires an active internet connection to use.

Are there any costs associated with using the Random String Generator?

No, the tool is completely free to use.

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