How to Generate Random Passwords Without an App
Sometimes you need a strong password but cannot or do not want to install an app. Whether you are on a restricted work machine, setting up a new device without your usual tools, or simply looking for a lightweight approach, there are several reliable methods to generate cryptographically random passwords without installing anything. This guide covers five practical methods — from browser-based tools to command-line one-liners — ranked by security and ease of use.
Method 1: Browser-Based Password Generator
The fastest and most accessible method is a browser-based generator that uses the Web Crypto API. Our Password Generator at WikiPlus is a single-page tool that runs entirely in your browser with no backend, no registration, and no data transmission. It uses crypto.getRandomValues — the same entropy source as TLS and other browser security features — so the randomness quality is equivalent to purpose-built security tools. Open the tool in any modern browser (Chrome, Firefox, Safari, Edge). Set your desired length (16 is a strong minimum), enable the character types you want, and click Generate. Copy the result with the copy button. The entire process is under 30 seconds. This method works on any device with a browser — desktop, mobile, tablet. It requires internet access to load the page initially, but once loaded, no further network activity occurs. If you want to be certain, open the page, disconnect from the network, and generate — it will work identically. The browser-based approach is the recommended option for most people. It is more accessible than command-line methods, more trustworthy than third-party apps with unclear data practices, and does not require any software installation.
Method 2: Command Line on macOS or Linux
If you have access to a macOS or Linux terminal, you can generate strong passwords with built-in command-line tools that require no additional installations. Using OpenSSL (available by default on macOS and most Linux distributions): openssl rand -base64 24 This generates 24 bytes (192 bits) of cryptographic randomness encoded in Base64, producing a 32-character string. The output uses letters, numbers, and the characters +, /, and = (from Base64 encoding). If you need to exclude those symbols, pipe through tr: openssl rand -base64 24 | tr -dc 'A-Za-z0-9!@#$%' | head -c 20 Using /dev/urandom directly: tr -dc 'A-Za-z0-9!@#$%^&*' < /dev/urandom | head -c 20 ; echo This reads from the system's cryptographically secure random source and filters characters to your chosen set, then takes the first 20 characters. Using Python (available on almost all Unix-like systems): python3 -c "import secrets, string; print(secrets.token_urlsafe(20))" The secrets module, introduced in Python 3.6, is explicitly designed for security-sensitive random generation. secrets.token_urlsafe() returns a URL-safe Base64-encoded string; secrets.choice() lets you build passwords from custom character sets. All three methods draw from the OS entropy pool (equivalent to crypto.getRandomValues in the browser) and are suitable for generating credentials.
Method 3: Command Line on Windows
Windows provides several built-in options for generating random passwords without installing anything. PowerShell (available on all modern Windows systems): -join ((65..90) + (97..122) + (48..57) + (33..47) | Get-Random -Count 20 | ForEach-Object {[char]$_}) This selects 20 random characters from the ASCII ranges covering uppercase letters, lowercase letters, digits, and symbols. Get-Random uses the .NET System.Security.Cryptography.RNGCryptoServiceProvider under the hood, which is a cryptographically secure generator. For a cleaner approach using .NET directly in PowerShell: $bytes = New-Object byte[] 20; [System.Security.Cryptography.RandomNumberGenerator]::Fill($bytes); [Convert]::ToBase64String($bytes).Substring(0,20) Windows Subsystem for Linux (WSL), if installed, gives you access to all the Linux methods above. WSL is available by default on Windows 10 and 11 via the Microsoft Store without third-party software. The built-in certutil command can also generate pseudo-random hex strings: certutil -generateSSTFromWU out.sst However, this is more complex and less clean than the PowerShell approach for password generation. For Windows users who prefer a graphical tool without installing an app, the browser-based method (Method 1) is simpler and equally secure.
Method 4: Physical Diceware for Offline Passphrases
If you want a passphrase that is provably generated without any electronic device, the diceware method uses physical dice to achieve verifiable cryptographic randomness. You need: a standard six-sided die (or five dice for speed) and the EFF diceware word list, which is freely downloadable and can be printed. The EFF list maps every possible 5-dice outcome (11111 through 66666) to one of 7,776 words. Roll five dice. Read the result as a 5-digit number — for example, 3, 1, 4, 2, 6 becomes 31426. Look up 31426 in the EFF word list to get your first word. Repeat this process five or six times to build a 5 or 6-word passphrase. This method produces genuinely random results that are physically verifiable — you can witness and log every roll. It is immune to all digital attack vectors: no software is involved, no entropy pool can be compromised, and no keylogger can observe the generation process. The result is a passphrase like 'timber vole crescent fridge humble radiant' — 6 words, approximately 77.5 bits of entropy (log2(7776) × 6), and significantly more memorizable than a random character string of equivalent security. Diceware is the gold standard for generating a master password you intend to memorize. The physical nature of the generation process provides a clear, trusted audit trail. Print the EFF word list, buy a cheap die, and generate your password offline. This is the approach recommended by security researchers who want absolute trust in their generation process.
Frequently Asked Questions
- Can I use a dice roll or coin flip to generate passwords?
- Yes — physical randomness from dice, cards, or coin flips is genuinely random and suitable for password generation. Dice are the most efficient: a standard six-sided die, rolled five times, maps to one of 7,776 words in the EFF diceware list. For random character passwords, you can construct a lookup table mapping dice outcomes to characters, but this is more complex than using the browser-based tool. Diceware passphrases are the most common productive use of physical randomness in password generation.
- Are online password generators trustworthy?
- A browser-based generator that runs locally (no server calls) and uses crypto.getRandomValues is trustworthy by design. You can verify this by opening your browser's Network tab in Developer Tools while using the tool — no requests should appear when you click Generate. Avoid generators that work as form submissions (the password appears in a URL), require an account, or cannot be verified to run entirely in the browser. Our tool can be used with network connectivity disabled as a simple verification test.
- How do I verify that a password generator uses real randomness?
- For browser-based tools, open the browser's developer tools, go to Sources, and inspect the JavaScript. Look for calls to crypto.getRandomValues() or window.crypto.getRandomValues(). This is the cryptographic API; its absence and the presence of Math.random() is a red flag. For command-line tools, openssl rand and Python's secrets module draw from the OS entropy pool, which you can verify by reviewing the official documentation. Physical dice are self-evidently random if rolled without manipulation.