🛠 Online Development Tools
Free browser-based development tools. All processing is done locally; your data never leaves your device.
Color Tools
Color Converter
HEX/RGB/HSL/CMYK conversion. Color picker, histogram generation, and WCAG contrast checking.
CSS Button Generator
Online CSS button style generator. Supports text, size, rounded corners, gradients, shadows, borders, hover/active states, and animation presets; generates CSS/HTML/SCSS code with a single click.
Encoding and Decoding
Base64 Encoding/Decoding
Base64 encoding and decoding. Supports text conversion, converting uploaded files to Data URIs, and URL-safe mode.
URL Encoding/Decoding
URL parameter encoding and decoding. `encodeURIComponent`, form mode, batch processing.
HTML Encoding/Decoding
HTML entity encoding and decoding, supporting three encoding formats, file upload and download, and a reference table of over 200 entities.
Formatting and Compression
Generation Tools
UUID Generator
Generates UUID v4 identifiers, with support for batch generation (up to 500), case conversion, multi-format output, and UUID format validation.
QR Code Generator
Generate QR codes for URLs, text, vCard business cards, Wi-Fi, and more. Customize colors, upload logos, and download high-resolution versions.
Token Calculator
LLM token estimation and cost calculation, supporting mainstream models such as GPT-4o, Claude, and DeepSeek.
ASCII Art Generator
A tool for converting images into ASCII art. Supports brightness/contrast/gamma adjustments, dithering, multiple character sets, color output, and batch processing. Runs entirely in the browser.
CSS Filter Generator
Adjust blur, brightness, contrast, grayscale, hue-rotate, invert, opacity, saturate, sepia, and drop-shadow in real time with 10 presets.
CSS Shadow Generator
Adjust X/Y offset, blur, spread, color, opacity, and inset shadows in real time. 8 presets, multi-layer shadows, one-click CSS.
Lucky Wheel
Customizable prizes, weight control, multiple color themes, draw history, and statistics. Smooth Canvas animation, fully client-side.
Code Tools
Code Highlighting Tool
Supports syntax highlighting for over 20 programming languages, multiple themes, line number display, copying HTML/text, file uploads, and exporting to HTML.
Code-Generated Image
Convert code snippets into beautifully formatted images with syntax highlighting. Supports 10 themes, 15+ programming languages, and a variety of fonts—perfect for sharing on social media and illustrating tech blogs.
Calculation Tools
Multi-Mode Calculator
Standard arithmetic operations, scientific calculations, number base conversions, expression evaluation, and unit conversions. Processed entirely in the browser.
BMI Calculator
Body Mass Index (BMI) calculator, supporting both metric and imperial units, WHO and Chinese standards, and BMR estimation.
Unit Converter
A versatile unit converter that supports real-time conversion between 13 categories of units, including length, weight, temperature, area, and volume.
Time Tools
Timestamp Converter
Convert between Unix timestamps and dates, with support for seconds/milliseconds precision, 15 world time zones, a time difference calculator, and batch conversion.
Crontab Generator
Visually build Cron expressions with Linux/Spring/Quartz formats, real-time parsing, execution preview, and timezone conversion.
Online Alarm Clock (Digital Clock)
Real-time clock with multiple alarms, stopwatch, and countdown timer. Fullscreen display, 5 ringtones, snooze, theme switching.
Hijri Date Converter
Convert between Gregorian and Islamic (Hijri) calendars with Kuwaiti/Umm al-Qura algorithms, holidays, and moon phases.
Text Tools
Regular Expression Testing
Test regular expressions in real time. Match highlighting, captured group extraction, replacement patterns, and 50+ common expressions.
Online Search and Replace
Text search and replace, with support for regular expressions, case-sensitive searches, batch replacement, and side-by-side comparison.
Text Sorting and Duplicate Removal
Sort and deduplicate text lines; supports 5 sorting modes, 4 deduplication modes, frequency statistics, and regular expression filtering.
ASCII Code Table Lookup
A complete ASCII code conversion table (0–255) that supports search and filtering, character conversion, and display in multiple number systems.
Markdown Mind Map
Generate interactive mind maps from Markdown text in real time. Node expand/collapse, zoom, pan, two-way editing, export PNG/SVG.
Text Encryption Tool
MD5/SHA1/SHA224/SHA256/SHA384/SHA512/SHA3 hashes, AES-256-CBC encrypt/decrypt, HMAC, Bcrypt, CRC32, and file checksum.