80+ free tools · No sign-up · 100% client-side

Free online tools for developers.

Format JSON, hash text, encode Base64, generate UUIDs, test regex and more — fast, private tools that run entirely in your browser. No uploads, no tracking.

✓ Free forever · ✓ No account needed · ✓ Your data never leaves your browser

Popular tools

JSON prettify and format — Prettify your JSON string into a friendly, human-readable format.
Hash text — Hash a text string using the function you need : MD5, SHA1, SHA256, SHA224, SHA512, SHA384, SHA3 or RIPEMD160
Base64 string encoder/decoder — Simply encode and decode strings into their base64 representation.
UUIDs generator — A Universally Unique Identifier (UUID) is a 128-bit number used to identify information in computer systems. The number of possible UUIDs is 16^32, which is 2^128 or about 3.4x10^38 (which is a lot!).
Token generator — Generate random string with the chars you want, uppercase or lowercase letters, numbers and/or symbols.
QR Code generator — Generate and download a QR code for a URL (or just plain text), and customize the background and foreground colors.

Learn with our guides

What Is JSON and How to Format It — JSON is the standard way apps exchange data on the web. Learn what JSON is, how its syntax works, and how to format, validate and minify it.
How to Generate a Strong Password — A strong password is long, random and unique. Learn what makes passwords crackable, how to generate secure ones, and how to manage them safely.
Base64 Encoding Explained — Base64 turns binary data into plain text so it can travel safely through email, JSON and URLs. Learn how it works, when to use it, and its limits.

Browse all guides →

All the tools

Crypto

Token generator — Generate random string with the chars you want, uppercase or lowercase letters, numbers and/or symbols.
Hash text — Hash a text string using the function you need : MD5, SHA1, SHA256, SHA224, SHA512, SHA384, SHA3 or RIPEMD160
Bcrypt — Hash and compare text string using bcrypt. Bcrypt is a password-hashing function based on the Blowfish cipher.
UUIDs generator — A Universally Unique Identifier (UUID) is a 128-bit number used to identify information in computer systems. The number of possible UUIDs is 16^32, which is 2^128 or about 3.4x10^38 (which is a lot!).
ULID generator — Generate random Universally Unique Lexicographically Sortable Identifier (ULID).
Encrypt / decrypt text — Encrypt clear text and decrypt ciphertext using crypto algorithms like AES, TripleDES, Rabbit or RC4.
BIP39 passphrase generator — Generate a BIP39 passphrase from an existing or random mnemonic, or get the mnemonic from the passphrase.
Hmac generator — Computes a hash-based message authentication code (HMAC) using a secret key and your favorite hashing function.
RSA key pair generator — Generate a new random RSA private and public pem certificate key pair.
Password strength analyser — Discover the strength of your password with this client-side-only password strength analyser and crack time estimation tool.
PDF signature checker — Verify the signatures of a PDF file. A signed PDF file contains one or more signatures that may be used to determine whether the contents of the file have been altered since the file was signed.

Converter

Date-time converter — Convert date and time into the various different formats
Integer base converter — Convert a number between different bases (decimal, hexadecimal, binary, octal, base64, ...)
Roman numeral converter — Convert Roman numerals to numbers and convert numbers to Roman numerals.
Base64 string encoder/decoder — Simply encode and decode strings into their base64 representation.
Base64 file converter — Convert a string, file, or image into its base64 representation.
Color converter — Convert color between the different formats (hex, rgb, hsl and css name)
Case converter — Transform the case of a string and choose between different formats
Text to NATO alphabet — Transform text into the NATO phonetic alphabet for oral transmission.
Text to ASCII binary — Convert text to its ASCII binary representation and vice-versa.
Text to Unicode — Parse and convert text to unicode and vice-versa
YAML to JSON converter — Simply convert YAML to JSON with this online live converter.
YAML to TOML — Parse and convert YAML to TOML.
JSON to YAML converter — Simply convert JSON to YAML with this online live converter.
JSON to TOML — Parse and convert JSON to TOML.
List converter — This tool can process column-based data and apply various changes (transpose, add prefix and suffix, reverse list, sort list, lowercase values, truncate values) to each row.
TOML to JSON — Parse and convert TOML to JSON.
TOML to YAML — Parse and convert TOML to YAML.
XML to JSON — Convert XML to JSON
JSON to XML — Convert JSON to XML
Markdown to HTML — Convert Markdown to Html and allow to print (as PDF)

Web

Encode/decode URL-formatted strings — Encode text to URL-encoded format (also known as "percent-encoded"), or decode from it.
Escape HTML entities — Escape or unescape HTML entities (replace characters like <,>, &, " and \' with their HTML version)
URL parser — Parse a URL into its separate constituent parts (protocol, origin, params, port, username-password, ...)
Device information — Get information about your current device (screen size, pixel-ratio, user agent, ...)
Basic auth generator — Generate a base64 basic auth header from a username and password.
Open graph meta generator — Generate open-graph and socials HTML meta tags for your website.
OTP code generator — Generate and validate time-based OTP (one time password) for multi-factor authentication.
MIME types — Convert MIME types to file extensions and vice-versa.
JWT parser — Parse and decode your JSON Web Token (jwt) and display its content.
Keycode info — Find the javascript keycode, code, location and modifiers of any pressed key.
Slugify string — Make a string url, filename and id safe.
HTML WYSIWYG editor — Online, feature-rich WYSIWYG HTML editor which generates the source code of the content immediately.
User-agent parser — Detect and parse Browser, Engine, OS, CPU, and Device type/model from an user-agent string.
HTTP status codes — The list of all HTTP status codes, their name, and their meaning.
JSON diff — Compare two JSON objects and get the differences between them.
Outlook Safelink decoder — Decode Outlook SafeLink links

Images and videos

QR Code generator — Generate and download a QR code for a URL (or just plain text), and customize the background and foreground colors.
WiFi QR Code generator — Generate and download QR codes for quick connections to WiFi networks.
SVG placeholder generator — Generate svg images to use as a placeholder in your applications.
Camera recorder — Take a picture or record a video from your webcam or camera.

Development

Git cheatsheet — Git is a decentralized version management software. With this cheatsheet, you will have quick access to the most common git commands.
Random port generator — Generate random port numbers outside of the range of "known" ports (0-1023).
Crontab generator — Validate and generate crontab and get the human-readable description of the cron schedule.
JSON prettify and format — Prettify your JSON string into a friendly, human-readable format.
JSON minify — Minify and compress your JSON by removing unnecessary whitespace.
JSON to CSV — Convert JSON to CSV with automatic header detection.
SQL prettify and format — Format and prettify your SQL queries online (it supports various SQL dialects).
Chmod calculator — Compute your chmod permissions and commands with this online chmod calculator.
Docker run to Docker compose converter — Transforms "docker run" commands into docker-compose files!
XML formatter — Prettify your XML string into a friendly, human-readable format.
YAML prettify and format — Prettify your YAML string into a friendly, human-readable format.
Email normalizer — Normalize email addresses to a standard format for easier comparison. Useful for deduplication and data cleaning.
Regex Tester — Test your regular expressions with sample text.
Regex cheatsheet — Javascript Regex/Regular Expression cheatsheet

Network

IPv4 subnet calculator — Parse your IPv4 CIDR blocks and get all the info you need about your subnet.
IPv4 address converter — Convert an IP address into decimal, binary, hexadecimal, or even an IPv6 representation of it.
IPv4 range expander — Given a start and an end IPv4 address, this tool calculates a valid IPv4 subnet along with its CIDR notation.
MAC address lookup — Find the vendor and manufacturer of a device by its MAC address.
MAC address generator — Enter the quantity and prefix. MAC addresses will be generated in your chosen case (uppercase or lowercase)
IPv6 ULA generator — Generate your own local, non-routable IP addresses for your network according to RFC4193.

Math

Math evaluator — A calculator for evaluating mathematical expressions. You can use functions like sqrt, cos, sin, abs, etc.
ETA calculator — An ETA (Estimated Time of Arrival) calculator to determine the approximate end time of a task, for example, the end time and duration of a file download.
Percentage calculator — Easily calculate percentages from a value to another value, or from a percentage to a value.

Measurement

Chronometer — Monitor the duration of a thing. Basically a chronometer with simple chronometer features.
Temperature converter — Degrees temperature conversions for Kelvin, Celsius, Fahrenheit, Rankine, Delisle, Newton, Réaumur, and Rømer.
Benchmark builder — Easily compare execution time of tasks with this very simple online benchmark builder.

Text

Lorem ipsum generator — Lorem ipsum is a placeholder text commonly used to demonstrate the visual form of a document or a typeface without relying on meaningful content
Text statistics — Get information about a text, the number of characters, the number of words, its size in bytes, ...
Emoji picker — Copy and paste emojis easily and get the unicode and code points value of each emoji.
String obfuscator — Obfuscate a string (like a secret, an IBAN, or a token) to make it shareable and identifiable without revealing its content.
Text diff — Compare two texts and see the differences between them.
Numeronym generator — A numeronym is a word where a number is used to form an abbreviation. For example, "i18n" is a numeronym of "internationalization" where 18 stands for the number of letters between the first i and the last n in the word.
ASCII Art Text Generator — Create ASCII art text with many fonts and styles.

Data

Phone parser and formatter — Parse, validate and format phone numbers. Get information about the phone number, like the country code, type, etc.
IBAN validator and parser — Validate and parse IBAN numbers. Check if an IBAN is valid and get the country, BBAN, if it is a QR-IBAN and the IBAN friendly format.