Case Converter
UPPER, lower, Title, sentence, camel, snake, kebab and alternating case in one click.
Word Counter
Count words, characters, sentences, paragraphs and estimate reading time as you type.
Text Diff Checker
Compare two texts and highlight every added or removed line instantly.
Sort & Deduplicate Lines
Sort lines alphabetically, remove duplicates, trim spaces and delete blank lines.
Number to Words Converter
Spell numbers in English or convert amounts to Chinese financial capital characters.
URL Slug Generator
Turn any title into a clean, SEO-friendly URL slug with your chosen separator.
JSON Formatter & Validator
Beautify, validate and minify JSON with clear error positions — all in your browser.
JSON to CSV / CSV to JSON
Convert JSON arrays to spreadsheets-ready CSV and back, including nested fields.
XML Formatter
Beautify and indent XML/SVG/HTML documents and validate well-formedness instantly.
YAML to JSON Converter
Convert YAML config files to JSON and back, with validation and error messages.
Markdown to HTML Converter
Write Markdown and instantly preview the rendered HTML, then copy the source.
SQL Formatter
Beautify and indent SQL queries with optional keyword uppercasing.
URL Encode / Decode
Percent-encode or decode URLs and query parameters safely and instantly.
Base64 Encode / Decode
Encode text and files as Base64 or decode data URLs — supports Unicode and images.
JWT Decoder
Decode JWT header and payload, inspect claims and expiry — tokens are never sent anywhere.
SHA Hash Generator
Generate SHA-1, SHA-256, SHA-384 and SHA-512 hashes from text with the Web Crypto API.
UUID Generator
Generate one or thousands of RFC-4122 v4 UUIDs instantly, with optional braces and uppercase.
Password Generator & Strength Meter
Create strong random passwords locally and measure their entropy in bits.
File Checksum Calculator
Calculate SHA-1/256/384/512 checksums of any file locally and compare against an expected hash.
CSV to Excel Converter
Turn CSV files into formatted .xlsx spreadsheets in your browser — no upload, no sign-up.
vCard Generator
Create a digital contact card (.vcf) ready to save on a phone or share by QR code.
Barcode Generator
Create CODE128, EAN-13, UPC, CODE39 and ITF barcodes as PNG or SVG, free.
QR Generator
Make QR codes for links and Wi-Fi.
Lorem Ipsum Generator
Generate placeholder paragraphs, sentences or words for mockups and designs.
SVG Minifier
Strip comments and redundant whitespace from SVG markup and download the smaller file.
SVG to React Converter
Turn raw SVG into a ready-to-paste React JSX component with camelCased attributes.
Image to Base64 Converter
Convert images to data URLs with ready CSS background and HTML snippets to copy.
Color Contrast Checker (WCAG)
Check text contrast ratios against WCAG 2.1 AA and AAA standards.
Cron Expression Explainer
Translate 5-field cron schedules into plain English and preview the next run times.
Device & Screen Tester
Show screen specs and run dead-pixel, keyboard, microphone and camera tests.
Statistics Calculator
Paste a data set to get mean, median, mode, range, variance and standard deviation.
GCD & LCM Calculator
Enter integers to get the greatest common divisor, least common multiple and prime factors.
Combination & Permutation Calculator
Enter n and r to compute nCr combinations, nPr permutations and factorials.
Subnet Calculator (CIDR)
Parse an IP/CIDR into network address, netmask, broadcast, host range and host count.
NPV & IRR Calculator
Enter a discount rate on the first line and cash flows below to compute NPV and IRR.
JSON to TypeScript Converter
Turn sample JSON into typed TypeScript interfaces instantly in your browser.
Text Redactor & Data Masker
Mask phone numbers, emails, Chinese ID cards and bank card numbers before sharing text.
URL Parser & Query Expander
Break URLs into protocol, host, port, path and every query parameter, one per line.
User-Agent Parser
Detect browser, engine, operating system and device type from a User-Agent string.
HTML Entities Encoder/Decoder
Encode text to HTML entities and decode entities back, with named or numeric output.
CSS Minifier
Strip comments, whitespace and redundant semicolons from CSS entirely in your browser.
Morse Code Translator
Translate text to International Morse code and decode Morse back to text, offline.
Keyword Density Analyzer
Count word frequencies and density percentages in your content, with the top terms ranked.
Readability Checker
Score English text with Flesch Reading Ease and grade-level formulas, plus sentence stats.
robots.txt Generator
Generate allow-all, block-all or custom robots.txt rules with an optional sitemap line.
Citation Generator (APA / MLA / GB-T)
Build APA 7, MLA 9 and GB/T 7714 references for books, websites and journal articles.
Typing Speed Test
Measure your typing speed in WPM and accuracy with timed English and code samples.
Chinese to Pinyin Converter
Convert Chinese characters to pinyin with tone marks, with or without the tones.
Traditional ↔ Simplified Chinese Converter
Convert text between traditional and simplified Chinese instantly with a local dictionary.