Free tools for creators and developers

Format, validate, and minify JSON online. Free, no signup — your data never leaves your browser.

Format SQL queries online — beautify MySQL, PostgreSQL, SQLite, SQL Server, Oracle, and BigQuery.

Beautify or minify HTML in your browser. Pure client-side — your markup never leaves your device.

Beautify or minify CSS rules instantly in your browser. Free, no signup, no upload.

Validate, reformat, and minify YAML in your browser. Catches syntax errors with line numbers.

Beautify or minify XML using your browser's native parser. No dependencies, fast and accurate.

Reformat Markdown with Prettier. Consistent spacing, list markers, and link layout.

Beautify with Prettier or minify in your browser. Supports modern syntax — async/await, optional chaining, JSX.

Clean up Python indentation, collapse blank lines, normalize string quotes. Indentation cleaner, not full PEP-8.

Reformat PHP source in your browser. PSR-12-friendly defaults, brace-style toggle, opener normalization.

Reindent Java source with K&R or Allman brace style. Pure client-side, no compile.

Reindent C# source with Allman braces, auto-property normalization, and expression-bodied member tidy-up. Indentation tidy, not a full Roslyn format.

Reindent C or C++ source — brace style, indent width, and preprocessor placement controls. Indentation tidy, not a full clang-format.

Reindent Ruby, Lua, or Perl source. One tool, three keyword-driven languages.

Pretty-print GraphQL queries, mutations, and SDL using the official graphql/language parser.

Convert between LESS, SCSS, SASS, Stylus, and CSS. Real compilers for "to CSS" paths, heuristics for the rest.

Minify JavaScript with terser. Mangle, compress, comment policies — and a before / after size comparison.

Minify HTML with html-minifier-terser. Collapses whitespace, removes comments, inline CSS / JS minification. Size savings shown live.

Convert CSV (or TSV / pipe-separated) data to JSON. Auto-detects delimiter, RFC 4180 compliant.

Convert a JSON array of objects to CSV. Optional dot-path flatten for nested data.

Convert JSON to YAML in your browser. YAML 1.2 spec.

Convert YAML to JSON in your browser. Catches syntax errors with parser messages.

Convert JSON to XML in your browser. Configurable root element, attribute prefix, and text key.

Extract one column from CSV, TSV, or any delimited text. Pick by column number or header name. RFC 4180 compliant.

Convert XML to JSON in your browser. Native DOMParser with configurable attribute prefix, text key, and compact mode.

Convert CSV (or TSV / pipe-separated) data to XML. Configurable root and record element names. Header row becomes column tags.

Generate INSERT statements from CSV. MySQL, PostgreSQL, SQLite, or SQL Server dialect, with optional CREATE TABLE.

Strip HTML tags and decode entities to plain text. Toggles for line breaks, links, and whitespace preservation.

Extract <table> elements from HTML into CSV, TSV, JSON, or Markdown. Picks individual tables when the page has more than one.

Convert HTML to Markdown using Turndown. ATX or Setext headings, bullet style, code-fence style — fully customizable.

Render Markdown to HTML with live preview. GFM tables, task lists, fenced code blocks. Powered by marked.

Generate a Java POJO from JSON. Toggles for Jackson annotations, Lombok, or Java 16+ records. Nested objects become nested classes.

Convert a Java POJO (Plain Old Java Object) instance into JSON using Jackson, Gson, or Moshi. Copy-paste-ready code recipes plus the reverse converter when you need to scaffold the POJO itself.

Encode and decode Base64 text or files. Supports standard and URL-safe variants. Free, no signup.

Encode and decode URLs and query string parameters. Percent-encoding for safe transmission.

Encrypt and decrypt text with AES-256-GCM and a password. PBKDF2-SHA256 key derivation, runs entirely in your browser.

Encode and decode Base16, Base32 (RFC 4648), Base32 Crockford, Base85 (ASCII85), and Base91 in your browser.

Convert text to UTF-8 hex bytes, decimal bytes, \xAB or \u{HEX} escape sequences — and back.

Encode and decode HTML entities — named, decimal, and hex. 250+ HTML5 entities included.

Escape and unescape strings for HTML, XML, Java, C#, JavaScript, JSON, CSV (RFC 4180), and SQL.

Compute MD5 digest of text or files (up to 50 MB) in your browser. Output in hex or Base64.

Compute SHA-256 digest of text or files in your browser using Web Crypto API. Output in hex or Base64.

Compute SHA-1 digest of text or files in your browser using Web Crypto API. Useful for Git commit hashes and legacy systems.

Classic ROT13 cipher in your browser. Encoding and decoding are the same operation.

Encrypt and decrypt with the classic Caesar shift cipher. Includes auto-detect using English letter frequency.

Compute MD4, MD5, SHA-1, SHA-224, SHA-256, SHA-384, SHA-512, SHA3, Keccak-256, CRC-32 and NTLM hashes of text or files in your browser.

Convert numbers between decimal, binary, octal and hexadecimal in a live 4-row grid. BigInt-safe with optional signed 32 / 64-bit mode.

AND, OR, XOR, NAND, NOR, XNOR, NOT and shift operations on two BigInt operands. Results shown in decimal, binary, octal and hex at once.

Convert IPv4 and IPv6 between dotted, decimal integer, hex, octal, binary, and canonical / expanded forms. Auto-detects the input format.

Convert text to UTF-8 hex bytes and back. Pick from five separators on encode; decode auto-strips any common separator.

Convert text to 8-bit binary and back. UTF-8 aware with optional byte and nibble spacing for readability.

Convert characters to ASCII / Unicode codepoints in decimal, hex, binary and octal — or render a live table for any input string.

Convert any date and time between IANA timezones. DST-aware, shareable, runs entirely in your browser.

Convert Unix timestamps (seconds or milliseconds) to ISO, UTC, RFC 2822, local, and relative formats. Live "Now" panel.

Translate a cron expression to plain English and preview the next 5 fire times. Supports standard 5-field and 6-field with seconds.

Test JSONPath expressions against your JSON. Live evaluator with path and value results, filters, slices, recursive descent.

Test XPath expressions against XML or HTML using your browser's native XPath engine. Live results table.

Generate 1–100 strings that match any regex pattern. Great for test data, fixtures, and fuzzing.

Validate JSON5 with line and column error reporting. Supports comments, trailing commas, single quotes, hex numbers.

Compare two blocks of text — side-by-side, inline, or unified patch. Line, word, or character granularity.

Structural JSON comparison. Color-coded paths for added, removed, and changed keys. Optional ignore-array-order mode.

Turn any text into a clean URL slug. Transliterates diacritics, strips punctuation, optional stopword removal.

Build GitHub Flavored Markdown tables in a live grid. Paste TSV or CSV, set alignment per column.

Build campaign-tagged URLs for Google Analytics, GA4, Plausible, PostHog. Validates URL and saves your last 5 locally.

Break a URL into scheme, credentials, host, port, path, query and hash. Percent-decoded query parameters in a live table.

Live HTML / CSS / JS playground with sandboxed iframe preview. Auto-saves to localStorage. Pure client-side.

Generate UUIDs online — v1, v4, v7, and Nil. Bulk generation up to 10,000. Free, no signup.

Generate strong, cryptographically random passwords. Configurable length and character sets — runs in your browser.

Generate fake JSON from a schema using faker.js. Multi-output: JSON, CSV, TSV, XML. Free, runs in your browser.

Obfuscate JavaScript with control-flow flattening, string array, dead-code injection and identifier mangling. Three presets, runs in your browser.

Convert text between 14 cases — UPPER, lower, Title, Sentence, camelCase, snake_case, kebab-case, CONSTANT_CASE, and more.

Sort lines alphabetically, numerically, by length, or just reverse. Locale-aware, case-insensitive and unique options.

Count word occurrences with rank, count, and percent. Stopword filter, top-N selector, CSV export of the full table.

Reverse text by character, word, or line. Grapheme-cluster safe — emoji and combining sequences stay intact.

Convert text into 13 Unicode font styles — bold, italic, script, fraktur, double-struck, monospace, fullwidth. Works on Twitter, IG, TikTok, Discord.

Generate invisible Unicode characters for Discord, gaming, and platforms that require non-empty input. Six variants.

Add Unicode strikethrough, underline, or overline to any text. Copy-paste to bios, posts, comments.

Convert text to Unicode small caps, superscript, or subscript. ᴄᴏᴘʏ ᴀɴᴅ ᴘᴀsᴛᴇ ᴀɴʏᴡʜᴇʀᴇ.

Flip text upside down with Unicode mirrored characters. Great for fun captions and bios.

Glitch your text with stacked combining diacritics. Mild for subtle creep, chaos for full Zalgo.

Strip diacritics from any text — café → cafe, naïve → naive. Optional German / Nordic transliteration (ä → ae, ß → ss, å → aa).

Remove or replace line breaks in text. Three modes — replace with space, keep paragraphs, or strip all.

Clean extra spaces, tabs, and blank lines. Optional zero-width Unicode strip catches sneaky invisible characters.

Remove duplicate lines from a list. Case-sensitive toggle, trim before compare, keep first or last, optional sort.

Keep or remove lines matching a substring or regex pattern. Invert match, case-insensitive, trim before match.

Repeat text 1–10000 times. Modes: whole block, per line, or per word. Separator picker with custom option.

Strip Unicode punctuation and symbols from text. Optional keep apostrophes, hyphens, periods; whitespace collapse.

Count words, characters, sentences, and paragraphs. Reading time, speaking time, and top keywords — instant.

Download YouTube thumbnails in all available resolutions. Just paste a video URL.

Generate Lorem Ipsum placeholder text — by paragraphs, sentences, or words. Optional HTML wrapping.

Paste a list, pick N at random. Unique-only mode, repeatable draws. Great for raffles, team assignments and lunch picks.

Convert colors between HEX, RGB / RGBA, HSL, HSV, and CMYK in a live grid. Swatch preview and CSS named-color lookup.

Convert between length, weight, volume, area, time, temperature, speed, data size, and angle units. Live grid across every unit in the dimension.

Convert JPG to lossless PNG entirely in your browser. Files never upload.

Convert PNG to JPG in your browser with quality control. Files never upload.

Convert WebP ↔ JPG / PNG in your browser. Files never upload. Smaller files for the modern web.

Shrink JPG, PNG, or WebP files. Before/after size shown side-by-side. Files never upload.

Resize images by width, height, percentage, or exact dimensions. Aspect ratio lock. Files never upload.

Paste CSV, get a live line chart. Multi-series, smooth curve slider, PNG export. Free, runs in your browser.

Build bar charts from CSV — stacked, grouped, horizontal. Multi-series, PNG export, no upload.

Two-column CSV in, pie chart out. Auto-coloured slices, PNG export, pure client-side.

Doughnut chart from CSV — perfect for KPI slides with a hollow centre. PNG export, no upload.

Scatter plot from CSV — first column X, every following column a Y series. PNG export, runs in your browser.

Add or subtract years, months, weeks, days, hours and minutes to a date — or compute the difference between two dates with business-day count.

Test how your URL appears when shared on social media. Preview Facebook, Twitter, LinkedIn, and Slack cards.

Generate cryptographically random integers — range, count, unique-only and decimal / binary / octal / hex output.

Animated bubble sort with step controls, speed, custom input, live comparison/swap counters and pseudocode. Runs entirely in your browser.

Animated insertion sort with step controls, speed, custom input, live comparison/write counters and pseudocode. Runs in your browser.

Animated selection sort with step controls, speed, custom input, live comparison/swap counters and pseudocode. Runs in your browser.

Animated merge sort with step controls, speed, custom input, live comparison/write counters and pseudocode. Runs in your browser.

Animated quicksort with pivot/partition highlights, step controls, speed, custom input, live counters and pseudocode. Runs in your browser.

Animated heap sort with step controls, speed, custom input, live comparison/swap counters and pseudocode. Runs in your browser.

Animated binary search over a sorted array with target input, step controls, speed, live comparison counter and pseudocode. Runs in your browser.

Animated linear search with target input, step controls, speed, live comparison counter and pseudocode. Works on unsorted data. Runs in your browser.

Interactive Dijkstra pathfinding on a grid — draw walls, move start/goal, generate mazes, step through the search. Runs in your browser.

Interactive A* pathfinding on a grid with a Manhattan heuristic — draw walls, move start/goal, generate mazes, step through the search. Runs in your browser.

Interactive breadth-first search on a grid — draw walls, move start/goal, generate mazes, step through the level-by-level expansion. Runs in your browser.

Interactive depth-first search on a grid — draw walls, move start/goal, generate mazes, step through the deep-dive exploration. Runs in your browser.

Animated maze generator using recursive division — step through the wall carving, adjust speed, regenerate. Pairs with the pathfinding visualizers. Runs in your browser.

Interactive binary search tree — insert, search, delete with an animated tree, step controls and pseudocode. Runs in your browser.

Interactive binary max-heap — insert and extract-max with animated sift-up / sift-down, step controls and pseudocode. Runs in your browser.

Interactive LIFO stack — push and pop with an animated top pointer and step controls. Runs in your browser.

Interactive FIFO queue — enqueue and dequeue with animated front/rear pointers and step controls. Runs in your browser.

Interactive singly linked list — insert head/tail, search, delete with animated pointer traversal and step controls. Runs in your browser.

Interactive hash table with separate chaining — insert, search, delete with animated hashing and collision chaining. Runs in your browser.

Animated Sieve of Eratosthenes on a number grid — marks primes and crosses out composites, with step controls. Runs in your browser.

Animated Euclidean algorithm — compute the GCD of two numbers step by step with the (a, b) → (b, a mod b) reduction. Runs in your browser.

Animated prime factorization as a factor tree — splits a number into prime factors step by step. Runs in your browser.

Animated Collatz (3n+1) sequence as a line chart — watch the trajectory climb and fall to 1. Step controls. Runs in your browser.

Animated Fibonacci sequence — each term is the sum of the previous two, built iteratively with step controls. Runs in your browser.

Animated convex hull (Andrew’s monotone chain) on a plane of points — push/pop construction with step controls. Runs in your browser.

Animated polygon area with the shoelace formula — sums signed triangle areas with step controls. Runs in your browser.

Animated line segment intersection — cross-product orientation tests plus the exact crossing point, with step controls. Runs in your browser.

Animated recursive Tower of Hanoi solver — moves disks in the minimum 2ⁿ−1 steps with step controls. Runs in your browser.

Animated N-Queens backtracking on a chessboard — try, place, conflict, and backtrack with step controls. Runs in your browser.

Animated 0/1 knapsack dynamic programming — fills the DP table cell by cell, highlighting dependencies, with step controls. Runs in your browser.

Interactive Conway’s Game of Life — draw cells, play generations, step, randomize. Runs entirely in your browser.

Three-in-one percentage calculator: X% of Y, X as a % of Y, and % increase/decrease. Instant, client-side.

Online scientific calculator — trig, log, powers, roots, factorial, π/e, DEG/RAD, with a proper expression parser. Client-side.

Add, subtract, multiply and divide fractions with automatic simplification, decimal and mixed-number output. Client-side.

Exact nCr, nPr and n! with big-integer precision. Client-side, no signup.

Solve quadratics (real/complex roots + discriminant) and 2×2 linear systems. Client-side.

Add, subtract, multiply, transpose matrices and find determinant & inverse (2×2 to 4×4). Client-side.

Generate a full truth table from a boolean expression (AND/OR/NOT/XOR/→/↔), up to 8 variables. Client-side.

Plot y = f(x) for any expression over a custom range — powers, trig, logs, roots. Client-side.

Add, subtract, dot, cross, magnitude, unit vector and angle for 2D/3D vectors. Client-side and instant.

Union, intersection, difference, symmetric difference plus subset/superset checks. Duplicates removed automatically.

Minimise 2–4 variable Boolean functions to simplest SOP with don’t-care support. Shows prime implicants.

Symbolic first and second derivatives plus a numeric definite integral (Simpson’s rule). Client-side.

Descriptive statistics — mean, median, mode, range, variance, SD, quartiles (sample & population). Client-side; data never leaves your device.

Convert a value to a z-score and a z-score to a percentile (standard normal). Client-side.

Single events, independent AND/OR, and the binomial distribution P(X=k)/P(X≤k)/P(X≥k). Client-side.

Least-squares best-fit line with r and R² and a live scatter plot. Client-side; your data stays private.

Mean, variance and sample/population standard deviation with the full working shown. Client-side and private.

Two-way Roman numeral converter (1–3999) with full validation. Client-side.

Greatest common divisor and least common multiple of any list of integers, exact. Client-side.

Generate APA 7, MLA 9, Chicago and Harvard citations for websites, books and journals — reference + in-text. Client-side.

Flesch Reading Ease and Flesch–Kincaid grade level, with word/sentence/syllable stats. Client-side; text never leaves your device.

Estimate reading and speaking time from text, with adjustable WPM. Client-side.

Live word/character/sentence/paragraph counts and a page estimate for essays. Client-side; your writing stays private.

Credit-weighted GPA on the 4.0 scale — add courses, grades and credits. Client-side; grades stay private.

Weighted grade from categories, plus “what do I need on the final”. Client-side.

Fairly split a class or team into random groups by count or by size. Re-roll any time. Client-side.

Build flashcard decks and study them shuffled with a score. Saved locally — no account needed.

Pomodoro focus timer with automatic work/break cycling, custom durations, chime and notifications. Settings saved locally.

Live countdown to your exam, deadline or test. Label and date saved on your device. Client-side.

Molar mass / molecular weight from a chemical formula (parentheses + hydrates) with a per-element breakdown. Client-side.

Interactive, searchable periodic table — 118 elements with atomic mass, number and category colors. Client-side.

SUVAT motion, projectile, Ohm’s law and ideal gas solvers in one place. Enter what you know, get the rest.

Count significant figures and round to N sig figs, with ambiguous trailing-zero detection. Client-side.

Convert numbers between decimal, scientific, E-notation and engineering notation. Client-side.