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var fastKeyGenerator = require("fast-key-generator")

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fast-key-generator v1.0.1

Simple utils library for key generation.


Simple utils library for API calls.

npm version npm downloads npm license


To install fast-key-generator - you can use npm or yarn package manager.
npm install fast-key-generator --save
yarn add fast-key-generator


The fast-key-generator library includes only one function generateKey. Below you can find the documentation for this function.

The generateKey function

The simple method for key generation.
The generateKey function takes only one parameter, which is an object.
The options parameter may includes the following fields:
NameTypeDefault valueDescription
sizenumber16Key size (without prefix).
prefixstring""Key prefix.
chartypestring"alpha"Can be one of "alpha", "numeric", "alphanum", "symbols".
chartsetstring""If you provide charset, then the generator will use the characters from this charset & ignore the chartype.
transformstring or function"none"Can be one of "none", "lower", "upper" or custom function that takes a key as the first argument & should return formatted key.
validatefunctionempty functionIf the function returns true, the generation process will be completed. If false, the generation process will start again until the function returns true.
excludearray of strings[]An array of strings that should not be keys.


import { generateKey } from 'fast-key-generator';

const key = generateKey();
// The key will be a string with a length of 16

import { generateKey } from 'fast-key-generator';

const key = generateKey({
  size: 1,
  prefix: 'key_',
  chartype: 'numeric',
  exclude: [

// The key will be "key_9"

import { generateKey } from 'fast-key-generator';

const key = generateKey({
  size: 1,
  prefix: 'key_',
  chartype: 'numeric',
  validate: (key) => key.includes('2')

// The key will be "key_2"
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