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Format and validate JSON with customizable indentation, right in your browser.

Decode the header and payload of a JSON Web Token (without verifying the signature).

Test regular expressions live against a text and inspect every match.

Validate JSON and pinpoint the exact error (line and column) when it's invalid.

Compare two JSON documents and see which keys were added, removed or changed.

Count words, characters, sentences and paragraphs, and estimate reading time.

Compare two texts line by line and highlight what was added and removed.

Remove duplicate lines from a text list while keeping the original order.

Sort lines of text alphabetically or numerically, ascending or descending.

Reverse a text letter by letter and check whether it's a palindrome.

Trim spaces, collapse repeated spaces and clean up blank lines.

Validate an IBAN with the official mod-97 checksum and show its country.

Analyze a password's strength and estimate its entropy in bits.

Indent and format XML to make it easy to read.

Translate a cron expression into a plain-language explanation.

Validate a card number with the Luhn algorithm and identify its brand.

Validate the check digit of EAN-13, UPC-A and EAN-8 barcodes.

Calculate the edit distance and similarity percentage between two texts.

Show the code point, UTF-8/UTF-16 bytes and HTML entity of every character.

Validate a UUID and detect its version and variant.

Calculate the contrast ratio between two colors and check WCAG AA/AAA compliance.

Analyze keyword and phrase density in a text for SEO.

Format or minify CSS instantly.

Format SQL queries with indentation and uppercase keywords.

Break a URL down into its parts, or build a query string from parameters.

Calculate the upcoming run times of a cron expression.

Trim a text to the ideal length for SEO meta descriptions without cutting words mid-way.

Look up the meaning of any HTTP status code.

Look up the MIME type of a file extension or vice versa.

Check whether a number is prime and show its factorization.

Calculate the union, intersection and difference between two text lists.

Validate a .env file and convert it to JSON.

Indent and format HTML, respecting void tags like <br> and <img>.

Paste raw HTTP headers and view them as a table.

Check whether two words or phrases are anagrams of each other.

Check your text against the character limits of X, Instagram, SMS and more.

Find repeated words within the same text.

Escape the special characters in a string so it can be used inside a regular expression.

Format numbers as currency, percentage, or with thousands separators, in any locale.

Compare two semantic versions and validate their format.

Generate the full list of IP addresses in a small CIDR block.

Check whether an IP address is public, private, loopback or link-local.

Find and replace text in bulk, with support for regular expressions.

Calculate the readability of a Spanish text using the Fernández Huerta formula.

Join multiple lines of text into one, removing line breaks.

Compare two CSV files cell by cell and highlight what changed.

Compare two texts and highlight the differences character by character.

Read the content of a QR code from an image, without uploading it anywhere.

Check whether an email address has a valid format.

Generate a git-style unified diff from two texts.

Extract emails, URLs and phone numbers from a block of text.

Validate a sitemap.xml's structure and count its URLs.

Turn a cookie string into a readable table of keys and values.

Pad a text to a fixed length with the character you choose.

Count the real visual characters in a text, including compound emoji.

Count the vowels, consonants and other characters in a text.

Reverse the word order of a sentence, without reversing the letters.

Remove all HTML tags from a text and keep only the content.

Parse a User-Agent string and extract the browser, OS and device type.

Look up the service associated with a well-known TCP/UDP port number.

Analyze the frequency of each letter in a text, useful for cryptanalysis and linguistics.

Wrap a text so no line exceeds a set number of characters.

Look up the meaning of the most common DNS record types (A, MX, TXT, CNAME...).

Compare two hashes or strings and check if they're identical, ignoring case and spaces.

Validate an NDJSON (JSON Lines) file line by line and pinpoint errors.

Add line numbers to the start of each line of a text.

Check whether a card expiration date (MM/YY) is valid and whether it has already expired.

Find the longest common substring between two texts.

Try all 25 possible shifts to crack a Caesar-ciphered text.

Extract a value from a JSON object using a path like a.b[0].c.

Alphabetically sort a query string's parameters, useful for comparing URLs.

Look up the meaning and UTC offset of timezone abbreviations (EST, CET, JST...).

Estimate the number of syllables in an English text.

Generate word n-grams from a text, useful for content analysis and SEO.

Find the most repeated words in a text and how many times they appear.

Find the longest word or words in a text.

Show a text's spaces, tabs and line breaks as visible symbols.

Generate unique UUID v4 identifiers instantly.

Generate secure, random passwords with customizable length and character sets.

Calculate MD5, SHA-1, SHA-256 and SHA-512 hashes of any text.

Generate Lorem Ipsum placeholder text by words, sentences or paragraphs.

Generate a QR code from text, a URL or any other data.

Generate random numbers within a range, with an option for unique values.

Turn any text into a clean, URL-friendly slug.

Encrypt and decrypt text with the Caesar cipher, including ROT13.

Generate meta tags, Open Graph and Twitter Card tags for a page's SEO.

Generate a robots.txt file with allow, disallow and sitemap rules.

Generate a sitemap.xml from a list of URLs.

Generate complementary, analogous, triadic and monochromatic palettes from a color.

Generate visual CODE128, EAN-13 and UPC barcodes.

Encrypt and decrypt text with AES-GCM and a passphrase, all in your browser.

Calculate the MD5, SHA-1, SHA-256 or SHA-512 hash of a file without uploading it anywhere.

Generate memorable Diceware-style passphrases.

Generate a deterministic UUID v5 from a namespace and a name.

Convert comma- or tab-separated data into an aligned Markdown table.

Generate and sign a JSON Web Token with HMAC-SHA256, all in your browser.

Generate random MAC addresses and validate the format of an existing one.

Generate a cURL command from a method, URL, headers and body.

Generate fake people (name, email, phone, address) for testing.

Generate Luhn-valid card numbers for development testing - not real cards.

Encrypt and decrypt text with the classic Vigenère cipher.

Randomly shuffle a list of items (Fisher-Yates).

Split a list of names into random, balanced groups.

Convert text to speech right in your browser, without uploading anything to a server.

Generate random IPv4 addresses.

Generate a random color in HEX, RGB and HSL with one click.

Generate random strings with the character set and length you choose.

Build a cron expression with visual controls, without writing the syntax by hand.

Generate an SVG placeholder image with the size and color you choose.

Generate test IBANs with valid check digits, for development and QA - not real.

Generate ULID identifiers, lexicographically sortable by time.

Generate short, random IDs with a customizable alphabet and length.

Generate the first terms of the Fibonacci sequence.

Encrypt and decrypt text with the Atbash cipher, reversing the alphabet.

Generate random numeric PIN codes of the length you choose.

Roll one or more dice with any number of sides.

Flip one or more coins, heads or tails.

Generate an acronym from the initials of a phrase.

Generate a scale of lighter and darker tones from a color.

Calculate the Soundex phonetic code of an English name or word.

Generate a linear or radial CSS gradient from several colors.

Generate the CSS box-shadow property with visual controls.

Generate the CSS border-radius property, controlling each corner separately.

Generate a cryptographically secure random secret key in hex and Base64.

Generate a .gitignore file by combining templates for different languages and editors.

Calculate the CRC32 checksum of a text.

Generate an HMAC of a message with a secret key, using SHA-1, SHA-256, SHA-384 or SHA-512.

Encrypt and decrypt text with ROT47, a ROT13 variant covering the full printable ASCII range.

Encrypt and decrypt text with the Baconian cipher, using sequences of A and B.

Encrypt and decrypt text with the Rail Fence cipher, a classic transposition cipher.

Generate a CSS clamp() function for fluid typography between two viewport sizes.

Generate a CSS cubic-bezier() function for custom animation easing curves.

Generate the CSS filter property by combining blur, brightness, contrast and more.

Calculate the Adler-32 checksum of a text.

Generate glitchy text with combining diacritical marks, Zalgo-style.

Turn a text upside down, letter by letter.

Turn regular text into circled letters and numbers (Ⓐ Ⓑ Ⓒ).

Generate random, unique lottery numbers within a range.

Generate a word search puzzle from a list of words.

Generate a random date within a range.

Generate random true/false values, with adjustable probability.

Encode and decode text to and from Base64 without leaving your browser.

Encode and decode text to safely use it inside URLs.

Write Markdown and preview the resulting HTML in real time.

Convert colors between HEX, RGB and HSL instantly.

Convert text between camelCase, snake_case, kebab-case, PascalCase and more.

Convert length, weight and temperature between the most common units.

Convert Unix timestamps to readable dates and back.

Convert numbers between binary, octal, decimal and hexadecimal.

Encode and decode HTML entities like &amp;, &lt; and &#39;.

Convert CSV to JSON and JSON to CSV, with support for quoted fields.

Convert text to binary code and binary back to text.

Translate text to Morse code and Morse code back to text.

Convert Arabic numerals to Roman numerals and back.

Convert a number into its written form in Spanish.

Convert JSON to YAML and YAML to JSON.

Convert an image into a Base64 string (data URL) without uploading it anywhere.

Paste a Base64 string and preview the resulting image.

Encode and decode text in Base32 (RFC 4648).

Generate a TypeScript interface from a JSON object.

Translate English text into Pig Latin.

Convert text to the NATO phonetic alphabet (Alpha, Bravo, Charlie…).

Convert between bits, bytes, decimal KB/MB/GB and binary KiB/MiB/GiB.

Convert a title to proper capitalization following AP/Chicago style.

Flatten a nested JSON into single-line keys, or rebuild it back.

Convert between CSS color names and their hex value.

Encode and decode text in URL-safe Base64 (RFC 4648 §5).

Convert a date and time between different time zones around the world.

Convert XML to JSON and JSON to XML, with support for attributes and repeated elements.

Convert a code block's indentation between tabs and spaces.

Strip Markdown syntax and leave only plain text.

Generate a JSON Schema from a sample JSON object.

Convert a cURL command into JavaScript fetch() code.

Convert HTML to Markdown, with support for the most common tags.

Convert and validate ISBN-10 and ISBN-13 book codes.

Encode and decode text in Base58, the format used by Bitcoin.

Convert CSS measurements between px, em, rem and pt.

Convert a text to sentence case, capitalizing only the start of each sentence.

Convert a URL slug back into a readable title.

Convert text to \uXXXX escape sequences and back.

Convert colors between RGB and CMYK (an approximation, not color-profile managed).

Encode and decode HTTP Basic authentication headers.

Convert an IPv4 address to its IPv6-mapped form (::ffff:a.b.c.d) and back.

Convert Markdown to HTML code, ready to copy.

Convert text between the QWERTY and Dvorak keyboard layouts.

Convert numbers between decimal and base36, used in short ID generators.

Convert between a spreadsheet's column number and column letter (A, B... AA, AB...).

Invert the uppercase and lowercase letters of a text, letter by letter.

Calculate your body mass index from your weight and height.

Calculate your exact age in years, months and days from your date of birth.

Calculate percentages, what percent one number is of another, and percentage changes.

Add or remove VAT/sales tax from an amount at any rate you choose.

Calculate the final price and savings after applying a discount percentage.

Calculate the tip, total, and how much each person owes when splitting the bill.

Calculate the monthly payment and total interest of a loan.

Calculate network, broadcast, mask and host range from an IP/CIDR.

Calculate the duration between two times of day, even across midnight.

Add or subtract days, weeks, months or years from a date.

Count business days between two dates, excluding weekends.

Calculate the ISO 8601 week number of any date.

Check whether a year is a leap year.

Calculate compound interest on an investment with optional periodic contributions.

Calculate the greatest common divisor and least common multiple of several numbers.

Solve quadratic equations ax² + bx + c = 0, including complex roots.

Calculate mean, median, mode, standard deviation and variance of a list of numbers.

Calculate how many units you need to sell to cover your fixed costs.

Calculate the return on investment and annualized ROI.

Convert an annual salary to an hourly rate and back.

Calculate the straight-line distance between two GPS coordinates.

Calculate the area and perimeter of circles, rectangles and triangles.

Calculate the time remaining until a specific date and time.

Generate a month-by-month loan amortization table.

Add, subtract, multiply and divide numbers in binary, octal, decimal or hexadecimal.

Calculate the final price after applying several successive discounts.

Compare two loan offers side by side and find out which one is cheaper.

Split a bill between several people and calculate who owes whom.

Calculate the present or future value of an amount of money at a given interest rate.

Calculate the check digit of an incomplete EAN-8, UPC-A or EAN-13 code.

Calculate the selling price from a profit margin or a markup.

Calculate the simple interest on a principal at a fixed rate over a term.

Simplify an aspect ratio and calculate the missing dimension.

Calculate a screen's pixel density from its resolution and size.

Estimate how many years it takes an investment to double based on its interest rate.

Calculate the compound annual growth rate between a starting and ending value.

Calculate permutations (nPr) and combinations (nCr) of a set of items.

Round a number up, down or to the nearest value, with the precision you choose.

Calculate the weighted average of a list of values and their weights.

Calculate the quartiles, interquartile range and outlier bounds.

Calculate your basal metabolic rate and daily calorie needs based on your activity level.

Calculate your pace per kilometer or mile from distance and time.

Convert a dog's age to human years using the current scientific formula.

Estimate calories burned during a physical activity based on your weight and duration.

Calculate your GPA from your grades and credits.

Calculate your Western zodiac sign from your date of birth.

Calculate your Chinese zodiac animal and element from your birth year.

Calculate the approximate moon phase for any date.

Add up hours worked from several clock-in/clock-out shifts.

Calculate progressive tax by applying customizable brackets and rates.

Calculate tiered sales commission with increasing rates.

Calculate the determinant of a 2x2 or 3x3 matrix.

Calculate the dot product, cross product, magnitude and angle between two 3D vectors.

Calculate all three angles of a triangle from its three sides.

Calculate the slope and distance between two points on a plane.

Calculate how much time and interest you save by paying extra toward your loan each month.

Split a number into N parts as evenly as possible, distributing the remainder.

Convert a Gregorian calendar date to a Julian day number and back.

Convert a nominal interest rate into its effective annual rate (APY) based on the compounding frequency.