A lightweight, dependency-free Dart package for generating random passwords made up of lowercase letters, uppercase letters, numbers, and symbols.

Features

• Generates a random password of any requested length.
• Mixes up to four character sets — lowercase, uppercase, numbers, symbols — chosen randomly per character.
• Each character set can be individually enabled or disabled.
• Zero external dependencies (uses only dart:math).
• Simple, single-method API.

Platform support

This package is written in pure Dart — it has no Flutter SDK dependency and no platform channels, native code, or dart:io/dart:html usage. As a result it works identically on every platform supported by Dart and Flutter:

Platform	Supported
Android	✅
iOS	✅
Web	✅
Windows	✅
macOS	✅
Linux	✅
Server / CLI (pure Dart)	✅

Because it only depends on dart:math, it can also be used in plain Dart projects (backend, CLI tools, scripts) that don't depend on Flutter at all.

Getting started

Requires Dart SDK ^3.11.5 (or a Flutter SDK that bundles it).

Add the package to your pubspec.yaml:

dependencies:
  flutter_random_password: ^1.0.1

Then run:

dart pub get
# or, in a Flutter project:
flutter pub get

Then import it:

import 'package:flutter_random_password/flutter_random_password.dart';

Usage

import 'package:flutter_random_password/flutter_random_password.dart';

void main() {
  final pass = RandomPass();

  // Generate a 12-character random password using all character sets.
  final password = pass.generate(total: 12);
  print(password); // e.g. "aB3!kZ9$mQ2#"

  // Generate a numeric-only 6-digit PIN.
  final pin = pass.generate(
    total: 6,
    hasAlphabet: false,
    hasAlphabetUpper: false,
    hasSymbol: false,
  );
  print(pin); // e.g. "482913"
}

See example/flutter_random_password_example.dart for a runnable example that generates 100 passwords of varying length (6–17 characters).

API

RandomPass implements FlutterRandomPasswordBase:

abstract class FlutterRandomPasswordBase {
  String generate({
    required int total,
    bool hasAlphabet,
    bool hasNumeric,
    bool hasAlphabetUpper,
    bool hasSymbol,
  });
}

generate(...) returns a random password exactly total characters long, built from the enabled character sets:

Parameter	Default	Character set
total	—	Password length (required)
hasAlphabet	true	Lowercase a-z
hasAlphabetUpper	true	Uppercase A-Z
hasNumeric	true	Digits 0-9
hasSymbol	true	Symbols !@#$%^&*()_+-={}|[]\:";'>?<,./`~

Throws an ArgumentError if:

• total is 0 or negative, or
• every has* flag is false (no character set left to draw from).

Additional information

• Package name is historical (flutter_random_password) but the package itself has no Flutter dependency — it works in any pure Dart project.
• Character composition per generated character is random and independent, so a password is not guaranteed to contain at least one character from every set (e.g. a short password could end up all digits by chance).
• Uses dart:math's default (non-seeded) Random, which is not cryptographically secure. Do not use this package to generate secrets such as encryption keys, tokens, or anything requiring cryptographic-strength randomness.
• Contributions and issues are welcome via the project repository.

License

Licensed under the MIT License © 2026 znd3v (zendevv.com).