JSON Patch Tool
Generate and apply RFC 6902 JSON Patch operations for JSON changes.
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JSON Patch Tool
Generate and apply RFC 6902 JSON Patch operations for JSON changes.
SM2 / SM3 / SM4 Toolkit
Use Chinese SM2, SM3, and SM4 algorithms for encryption, hashing, signing, and verification.
JWT Generator
Generate JWT tokens with HS256, HS384, or HS512 secrets for API debugging.
RSA Key Generator
Generate RSA-OAEP or RSA-SHA256 public/private key pairs locally in the browser and export PEM.
JWT Decoder and Verifier
Decode JWT headers and payloads, with optional HMAC-SHA256 signature verification.
RSA Encryption and Signature Tool
Use PEM public/private keys for RSA-OAEP encryption/decryption and RSA-SHA256 signing/verification.
HMAC and SHA Hash Generator
Generate MD5, SHA1, SHA256, SHA512, and HMAC digests.
AES Encrypt / Decrypt
Encrypt and decrypt text locally with AES-GCM or AES-CBC, with Base64 and Hex output.
CSV Toolkit
Convert CSV and JSON with quoted-field support.
HTML to Markdown
Convert HTML fragments into Markdown text for rich text cleanup, article drafts, and web snippets.
Markdown to HTML
Convert Markdown text to copyable HTML fragments.
HTML Entity Encoder and Decoder
Encode and decode HTML entities for special characters.
CSS Generator
Generate common CSS snippets such as border radius and shadows with live preview.
TOML Parser
Parse TOML key-value configuration into JSON.
ENV Parser
Parse .env key-value configuration into JSON.
SQL Table Documentation
Generate Markdown field documentation from CREATE TABLE SQL.
JSON Mock Generator
Generate mock data from a JSON sample structure.
ID Generator
Generate UUID, ULID-style, and NanoID-style identifiers.
Regex Cheatsheet
Browse and copy common regular expression templates.
MIME Type Lookup
Look up common MIME types by file extension.
HTTP Status Code Lookup
Look up meanings of common HTTP status codes.
User-Agent Generator
Generate common browser and device User-Agent strings.
Regex Generator
Generate regular expressions from common templates such as email, URL, IP, date, and password.
Regex Explainer
Explain regex tokens including groups, quantifiers, character classes, and anchors.
JSON Toolkit
Access JSON editing, repair, model conversion, and Schema generation tools in one place.
JSON Repair
Repair trailing commas, single quotes, comments, unquoted keys, and other common JSON syntax problems.
JSON to TypeScript
Generate TypeScript interface definitions from JSON data in your browser.
JSON to Go Struct
Generate Go structs with JSON tags from JSON data in your browser.
JavaScript Formatter / Minifier / Obfuscator
Format, minify, obfuscate, deobfuscate, encode, decode, and validate JavaScript online.
JSON to Java
Generate Java POJO classes from JSON data in your browser.
CSS Formatter / Optimizer / Minifier
Format, optimize, compress, decompress, and tidy CSS online.
JSON to Pydantic
Generate Python Pydantic models from JSON data in your browser.
JSON to C#
Generate C# model classes from JSON data in your browser.
HTML Formatter / Minifier / HTML to JS
Format, minify, preview, and convert HTML to JavaScript online.
JSON Schema Generator
Generate JSON Schema from JSON data in your browser.
JSON Diff
Compare two JSON documents by field and array index to find added, removed, and changed values.
JSON to XML
Convert JSON data to structured XML in your browser.
JSON Editor
Format, validate, parse, highlight, and edit JSON online.
JSONPath Online Query
Query JSON with JSONPath expressions and inspect matching paths and values.
Unix Timestamp Converter
Convert Unix timestamps to local time and date time back to timestamps.
XML Formatter / Minifier / XML to JSON
Format, minify, clean, and convert XML to JSON online.
YAML to JSON
Convert YAML documents to JSON online.
IP Address Lookup and Calculator
Look up IP locations, convert IP addresses to integers, and calculate subnet ranges.
MD5 Hash Generator
Generate 32-bit and 16-bit MD5 hashes online.
Base64 Encoder / Decoder
Encode and decode Base64 for text and images online.
UTF-8 Encoding Converter
Convert UTF-8 encoded text and Chinese text online.
Unicode Converter
Convert Chinese text and Unicode escape sequences online.
URL Encoder / Decoder
Encode and decode URL strings online.
Word to HTML Converter
Paste Word content, clean generated HTML, and edit rich text online.
Markdown Editor
Write and preview Markdown content online.
Cron Expression Editor
Visually parse and generate Quartz cron expressions online.
Linux Command Reference
Search and browse Linux command usage online.
Online API Testing Tool
Debug HTTP APIs with methods, parameters, headers, body, and response display.
Online Base Converter
Convert numbers between binary, octal, decimal, hexadecimal, base32, base36, and base62.
Random String Generator
Generate random strings, passwords, and batches of passwords online.
Regex Tester
Test and debug regular expressions online.
User Agent Parser
Parse browser, OS, and device information from a User Agent string.
UUID Generator
Generate UUID values online.
JavaScript Runner
Run JavaScript snippets online and view console output.
SQL Formatter and Minifier
Format and minify SQL statements online.
Online Font Format Converter
Online Font Format Converter is an online utility for quick browser-based use.
Daily Life Tools
Date Difference Calculator
Calculate days, weeks, and hours between two dates.
Workday Calculator
Calculate an end date by workday count while skipping weekends.
Age Calculator
Calculate age in years and total days lived from a birthday.
BMI Calculator
Calculate BMI from height and weight with category reference.
Chinese ID Number Lookup
Validate Chinese ID numbers and parse region, birth date, gender, and validity.
Chinese Kinship Calculator
Calculate Chinese kinship terms quickly and accurately.
World Clock and Time Zone Converter
View world clocks and convert times across time zones.
Package Tracking
Package Tracking is a practical daily-life lookup or calculator tool.
Mobile Number Location Lookup
Mobile Number Location Lookup is a practical daily-life lookup or calculator tool.
Chinese License Plate Code Lookup
Look up Chinese vehicle plate province abbreviations and area codes.
Typing Practice Software
Practice typing, memorize words, and build English keyboard muscle memory.
Chinese Zodiac Lookup
Look up Chinese zodiac signs by birth year, age, or zodiac animal.
Mortgage Calculator
Calculate commercial, provident fund, and combined mortgage repayment plans.
Text and Document Tools
Simplified / Traditional Chinese Converter
Convert between Simplified Chinese and Traditional Chinese.
Word and Character Counter
Count characters, words, numbers, punctuation, lines, and paragraphs.
Online Text Diff Tool
Compare two texts or code snippets and highlight differences online.
Number to Chinese Numerals
Convert Arabic numbers to lowercase or uppercase Chinese numerals.
RMB Uppercase Amount Converter
Convert numeric amounts to uppercase Chinese RMB text for financial documents.
English Case Converter
Convert English text between uppercase, lowercase, title case, sentence case, and toggle case.
Online Text Deduplicator
Remove duplicate lines, blank lines, inline duplicates, and extra spaces.
Automatic Text Typesetting
Automatically improve Chinese-English mixed typography and spacing.
Chinese to Pinyin Converter
Convert Chinese characters to pinyin with or without tones.
Text Similarity Checker
Compare text similarity using cosine similarity and SimHash Hamming distance.
Add or Remove Line Numbers
Add or remove line numbers from text or code.
Word to HTML Converter
Paste Word content, clean generated HTML, and edit rich text online.
Markdown Editor
Write and preview Markdown content online.
Online Batch File Renamer
Rename local files and folders in batch with preview and custom rules.
PDF All-in-One Toolkit
PDF All-in-One Toolkit is an online text or document utility for editing, conversion, formatting, comparison, or processing.
Random String Generator
Generate random strings, passwords, and batches of passwords online.
File Hash Calculator
Calculate MD5, SHA1, SHA256, SHA512, SHA3, and other file hashes locally in the browser.
Image Tools
Color Converter
Convert HEX, RGB, and HSL color formats with preview.
Image Palette Extractor
Extract dominant HEX colors from local images.
Barcode Generator
Generate Code 128 barcode images and Data URLs.
Barcode Scanner
Scan barcodes from uploaded images when supported by the browser.
US Visa Photo 2×2 Inch Requirements
Check the official 2×2 inch US visa photo size, white background, and head dimensions.
Canada Visa Photo 35×45 mm Requirements
Check Canada temporary resident visa photo dimensions, head size, and background rules.
Singapore Passport Photo 35×45 mm Requirements
Check Singapore passport photo size, white background, and head dimensions.
Malaysia Passport Photo 35×50 mm Requirements
Check Malaysia passport photo size, white background, face dimensions, clothing, and live-capture requirements.
Japanese Rirekisho Photo 30×40 mm Guide
Check the common 30×40 mm Japanese resume photo format and clothing guidance.
Online SVG Maker
Create SVG drawings online.
Online Batch Image Cropper
Crop images online with custom ratios, rotation, zoom, batch processing, and ID photo presets.
Online Batch Image Compressor
Compress and convert JPEG, PNG, WEBP, AVIF, SVG, and GIF images in the browser.
Iconify Free Icon Library
Iconify Free Icon Library is an online image tool for editing, conversion, generation, compression, or visual design.
iconfont
iconfont is an online image tool for editing, conversion, generation, compression, or visual design.
Online App Icon Designer
Create and customize app icons with borders, colors, shadows, and export options.
Online QR Code Generator
Generate QR codes online.
Online QR Code Scanner
Scan and decode QR codes from images or camera input.
Captioned Image Maker
Add large captions to images and export captioned pictures.
Online Image Watermark Tool
Add text watermarks to images with custom color, opacity, size, and spacing.
Online Image Format Converter
Convert images between PNG, JPEG, GIF, BMP, WEBP, TIFF, ICO, AVIF, and more.
Online 3x3 Image Grid Generator
Split images into a 3x3 grid for social sharing and batch download.
Placeholder Image Generator
Generate placeholder images with custom size, text, and colors.
Online ICO Icon Maker
Convert PNG or JPG images to transparent ICO files with multiple sizes and rounded corners.
Online AI Background Remover
Remove image backgrounds with AI and export transparent PNG results.
Online ID Photo Maker
Create standard ID photos with smart background removal and multiple sizes.
Online EXIF Viewer
View photo EXIF metadata such as camera, shooting parameters, and GPS location.
Image Rounded Corner Maker
Add rounded corners to images and export the processed result.
Video Tools
Video Info Viewer
Read duration, resolution, file size, and basic metadata locally in your browser.
Video Cover Extractor
Choose a timestamp and export a PNG cover image from a local video.
SRT / VTT Subtitle Converter
Convert subtitles between SRT and WebVTT for publishing and editing workflows.
Video Bitrate Calculator
Calculate a recommended video bitrate from duration and target file size.
FFmpeg Command Generator
Generate common FFmpeg commands for compression, trimming, cover extraction, and GIF clips.
Platform Video Specs
Check recommended video ratios and specs for TikTok, Xiaohongshu, Bilibili, YouTube, and more.
Science and Education
Chinese Writing Practice for Kids
Practice common Chinese characters with stroke-order checking, audio, and rewards.
Periodic Table
Browse 118 chemical elements with atomic number, symbol, and Chinese name.
China 211 / 985 University Lookup
Browse China Project 211 and Project 985 university information.
Byte Unit Converter
Convert bit, B, KB, MB, GB, TB, PB, and other data units.
Temperature Converter
Convert Celsius, Fahrenheit, Kelvin, Rankine, and Reaumur temperature units.
Chinese Dynasties Timeline
Browse Chinese dynasties with periods, capitals, locations, and founders.
Chinese Character Stroke Demo
View Chinese character stroke animations, radicals, structure, pinyin, pronunciation, and homophones.
Chinese Character and Pinyin Quiz
Practice matching Chinese characters, pinyin, and pronunciation with quick quizzes.
Fun and Leisure
Today Hot Rankings
Today Hot Rankings is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Tetris
Play classic Tetris in the browser.
Flappy Bird
Flappy Bird is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Retro Game Collection
Retro Game Collection is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Puzzle Game Collection
Puzzle Game Collection is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
CrazyGames
CrazyGames is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Bouncy Balls
Bouncy Balls is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Live Earth View
Live Earth View is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
100,000 Stars
100,000 Stars is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Panoramic Forbidden City
Panoramic Forbidden City is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
All History
All History is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
Skyline Webcams
Skyline Webcams is a fun or leisure website for games, hot topics, live views, history, or casual browsing.
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