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Password Generator

Generate strong random passwords with full control over length, character sets, symbols and ambiguous characters, or build word-based passphrases. Shows the entropy and a crack time estimate for every result, and can produce a whole batch at once.

Everything runs locally in your browser. Your data never leaves your device.

Character sets

Strength

Very strong

102 bits of entropy. Average time to crack at 10,000,000,000 guesses per second: longer than the age of the universe.

Result

  • Generating…

Next steps

Send this tool's output straight into another tool.

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more, each with its own copy button.

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

Convert between scientific notation and full numbers as you type. Reads 1.23e5, 1.23 × 10^5 and plain numbers, shows the value written out, in normalized scientific notation and in engineering notation, and can round to any number of significant digits.

Sort the lines of a text alphabetically, naturally, by length, by numeric value or shuffled. Reverse the order with a switch, and optionally trim lines, drop blank lines and remove duplicates in the same pass.

Convert a color between HEX, RGB, HSL, HSV, HWB, CMYK, OKLCH and OKLAB. Type into any field and the others update as you go, or pick the color visually. Reads CSS color syntax and keeps alpha where the format supports it.

Check two colors against the WCAG contrast rules. Type or pick a text and a background color, read the contrast ratio, see which AA and AAA checks pass, preview real text at the sizes WCAG distinguishes, and get suggested fixes when a check fails.

Create a QR code for text, a link, an email, a phone number, an SMS, Wi-Fi access or a contact card. Set the error correction level, size, margin and colors, then download it as PNG or SVG or copy it straight to the clipboard.

Paste a cron expression and get a plain English explanation, a field by field breakdown and the next times it would run, in your local timezone or UTC. Reads five field crontab syntax, six fields with seconds, names like MON and macros like @daily.

Work out an IPv4 or IPv6 network from an address with a prefix or netmask: network and broadcast addresses, usable host range, subnet mask, wildcard mask and address type. Adjust the prefix with a slider, read the binary breakdown, and split the network into smaller subnets.

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

Encode text for use in URLs or decode percent-escaped strings back to readable text. Choose component, full-URL or form encoding, unwrap double-encoded strings, and break a URL into its parts with every query parameter decoded.

Convert Unix timestamps in seconds, milliseconds, microseconds or nanoseconds to readable dates in your local time, UTC or any timezone, and turn any date back into a timestamp. Shows the live current timestamp and relative time.

Escape text into HTML entities or decode entities back to plain text. Choose named or numeric entities, escape only the unsafe characters or everything outside ASCII, and read the result live.

Paste a JSON Web Token to see its header and payload as formatted JSON, with the token color coded so each part maps to its output. Explains the registered claims, shows expiry as readable dates, flags expired tokens and can verify the signature with a secret or public key.

Compress text or a file with gzip, deflate, brotli or Zstandard and see the size before and after, the compression ratio and how long it took. One click tries every method and recommends the smallest result.

Decompress gzip, deflate, brotli or Zstandard data from a file or pasted Base64 and read the result as text or download it. Detects the format from the magic bytes where possible, with a manual override.

About the Password Generator

This tool generates strong random passwords and word-based passphrases. Pick random characters with full control over length, character sets and symbols, or build a passphrase from real words that is far easier to remember and type.

Every draw comes from a cryptographically secure random number generator, and the strength meter shows the entropy in bits plus an honest estimate of how long cracking would take.

What you can do

  • Generate a strong random password with lowercase, uppercase, digits and symbols.
  • Set the exact length, from 4 to 128 characters.
  • Edit the symbol set, or exclude ambiguous characters like 0, O, 1, l and I.
  • Build a memorable diceware-style passphrase from the EFF short wordlist.
  • Check the entropy and estimated crack time of your settings.
  • Generate up to 100 passwords at once, then copy or download the whole batch.

How to use the Password Generator

  1. 1Pick a mode: random characters or a passphrase.
  2. 2Tune the settings. Length and character sets in one mode, word count, separator and capitalization in the other.
  3. 3Read the strength meter to see the entropy and how long cracking would take.
  4. 4Copy a password with the button next to it, or regenerate until you get one you like.
  5. 5For a batch, set how many you need and use Copy all or Download.

How the randomness works

Every character and word is drawn from the Web Crypto API's cryptographically secure random number generator, the same source password managers use. Draws go through rejection sampling, so no character is ever slightly favored the way a naive modulo mapping would. Math.random is never involved.

The option to require one character from each enabled set picks those characters first, fills the rest from the full pool, and then shuffles the result with the same secure randomness, so the guaranteed characters end up at unpredictable positions.

What the entropy number means

Entropy measures how many equally likely outputs the current settings can produce. Each extra bit doubles the number of guesses an attacker needs, so a 60-bit password is a billion times harder to crack than a 30-bit one. The meter computes the exact keyspace of your settings, including the small reduction caused by requiring a character from every set.

The crack time assumes an offline attacker testing ten billion guesses per second, which matches a serious GPU rig attacking a fast hash. Sites that store passwords with a slow hash, or that rate-limit login attempts, push the real time far higher. The estimate is the average case, half the keyspace searched.

Random characters or a passphrase

Random character strings pack the most entropy per character, which suits anything a password manager fills in for you. Passphrases trade some length for memorability. The words come from the EFF short wordlist, 1,296 short common words picked to be easy to spell, and each word adds about 10.3 bits. Five words reach roughly 52 bits and six words about 62, a solid choice for a password you actually have to type or remember.

Verify a checksum online: drop a file, paste the expected checksum and see instantly whether they match. The hash type is detected from the checksum itself, covering MD5, SHA-1, SHA-256, SHA-512, BLAKE3, CRC-32 and more, and sha256sum lines or whole checksum files can be pasted as-is.

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

Paste a JSON Web Token to see its header and payload as formatted JSON, with the token color coded so each part maps to its output. Explains the registered claims, shows expiry as readable dates, flags expired tokens and can verify the signature with a secret or public key.