Tech & Development
Everyday utilities for building and shipping, without leaving your browser or your data behind.
Encoding & Data
13JSON Formatter
Beautify, minify, and validate JSON in your browser.
Open calculatorBase64 Encoder / Decoder
Encode or decode Base64 text, with correct UTF-8 handling.
Open calculatorBase32 Encoder / Decoder
Encode or decode Base32 text per RFC 4648 — used by TOTP authenticator secret keys.
Open calculatorBase58 Encoder / Decoder
Encode or decode Base58 text — the same alphabet Bitcoin addresses use.
Open calculatorURL Encoder / Decoder
Percent-encode or decode text for safe use in a URL.
Open calculatorJWT Decoder
Decode a JSON Web Token’s header and payload — no signature verification.
Open calculatorNumber Base Converter
Convert a number between binary, octal, decimal, and hexadecimal at once.
Open calculatorCSV to JSON Converter
Convert CSV to JSON, with correct handling of quoted fields and embedded commas.
Open calculatorJSON to CSV Converter
Convert a JSON array of objects to CSV, with correct quoting for commas and quotes.
Open calculatorUUID Shortener (Base62 Encoder)
Shorten a UUID to a compact base62 string for URLs, or expand it back.
Open calculatorHex to Base64 Converter
Convert hex-encoded bytes to Base64, or Base64 back to hex.
Open calculatorString Byte Size Calculator
Character count, UTF-16 code unit length, and UTF-8 byte size, all at once.
Open calculatorHTML Entity Encoder / Decoder
Escape special characters into HTML entities, or decode them back to text.
Open calculatorGenerators
7Password Generator
Generate strong, random passwords using your browser’s crypto API.
Open calculatorUUID Generator
Generate RFC 4122 v4 UUIDs in bulk, right in your browser.
Open calculatorHash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes using the Web Crypto API.
Open calculatorLorem Ipsum Generator
Generate placeholder text by paragraph, sentence, or word count.
Open calculatorMarkdown Table Generator
Paste comma- or tab-separated data and get a properly formatted, escaped Markdown table.
Open calculatorRandom Number Generator
Cryptographically random integers in any range, with or without duplicates.
Open calculatorSlug Generator
Turn any title or sentence into a clean, URL-safe slug.
Open calculatorText & Strings
8Regex Tester
Test patterns against sample text with live match highlighting.
Open calculatorWord & Character Counter
Live word, character, sentence, and paragraph counts with reading time.
Open calculatorText Case Converter
Convert text to camelCase, snake_case, kebab-case, and more at once.
Open calculatorText Diff Checker
Compare two blocks of text line by line and see what was added, removed, or unchanged.
Open calculatorLevenshtein Distance Calculator
Edit distance and similarity percentage between two strings.
Open calculatorRoman Numeral Converter
Convert numbers to Roman numerals and back, validated against the canonical subtractive rules.
Open calculatorString Escape Tool
Escape a string for use as a JS/JSON string literal or a regex pattern.
Open calculatorSMS Character & Segment Counter
Count characters and SMS segments for a text message, detecting GSM-7 vs UCS-2 encoding.
Open calculatorWeb & Design
11Color Contrast Checker
WCAG contrast ratio with AA/AAA pass and fail badges.
Open calculatorColor Converter
Convert a color between HEX, RGB, and HSL.
Open calculatorCSS Gradient Generator
Build a linear or radial CSS gradient with a live preview and one-click copy.
Open calculatorCSS Box Shadow Generator
Build a CSS box-shadow value with a live preview and one-click copy.
Open calculatorColor Palette Generator
Generate a complementary, triadic, analogous, or monochromatic palette from any color.
Open calculatorCSS Unit Converter
Convert between px, rem, em, pt, and % using your base font size.
Open calculatorCSS Specificity Calculator
See exactly which CSS rule wins a conflict — ID, class, and type selector counts.
Open calculatorCSS Fluid Clamp() Calculator
Generate a clamp() value that scales smoothly between a min and max size across a viewport range.
Open calculatorAspect Ratio Calculator
Simplify ratios or solve for a missing width or height.
Open calculatorMeta Tag & SEO Preview Generator
Generate title, description, and Open Graph meta tags with a live search-result preview.
Open calculatorPixel to Print Size (DPI) Calculator
Convert pixel dimensions to physical print size in inches and centimeters at any DPI.
Open calculatorDate & Time
5Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates.
Open calculatorTimezone Converter
Convert a date and time across major world time zones at once, with correct DST handling.
Open calculatorCron Expression Explainer
Parse a cron expression into a plain-English schedule and see its next run times.
Open calculatorWorking Days Between Two Dates
Count the weekdays between two dates, excluding weekends.
Open calculatorDate Difference Calculator
The exact years, months, weeks, and days between any two dates.
Open calculatorValidators
6Semantic Version (SemVer) Comparator
Compare two version strings and see exactly why one outranks the other, per semver.org.
Open calculatorEmail Format Validator
Check whether a string is a structurally valid email address, with a specific reason when it fails.
Open calculatorPassword Crack Time Calculator
See how long a brute-force attack would take to guess your password.
Open calculatorLuhn Algorithm Checksum Validator
Validate a card number's Luhn (mod-10) checksum — the same algorithm every card network uses.
Open calculatorCredit Card Type Detector
Detect a card network — Visa, Mastercard, Amex, Discover, and more — from its number prefix.
Open calculatorIBAN Validator
Validate an IBAN's ISO 7064 MOD97-10 checksum — the same algorithm every bank uses.
Open calculatorWeb & Network
4URL Parser
Break a URL down into protocol, host, port, path, query parameters, and hash.
Open calculatorSubnet Calculator
Network address, broadcast address, subnet mask, and usable host range for any IPv4 CIDR block.
Open calculatorHTTP Status Code Reference
Look up any HTTP status code — what it means, its category, and when servers return it.
Open calculatorMIME Type Lookup
Look up the MIME (media) type for any common file extension.
Open calculatorMath & Geometry
5Quadratic Equation Solver
Solve ax² + bx + c = 0 for real or complex roots, with the discriminant shown.
Open calculatorGCD & LCM Calculator
Greatest common divisor and least common multiple of two or more integers.
Open calculatorStandard Deviation & Variance Calculator
Mean, variance, and standard deviation of a data set — population or sample.
Open calculatorPermutations & Combinations Calculator
nPr and nCr for any n and r, computed without factorial overflow.
Open calculatorPrime Factorization Calculator
Break a number into its prime factors, and check whether it’s prime.
Open calculator