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Text Tools

ASCII Art Generator

Free online ASCII Art generator. Convert text into beautiful character art with multiple font styles. Perfect for code comments, README files, and terminal banners.

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Base64 Encoder/Decoder

Encode and decode text using Base64

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Case Converter

Free online case converter tool. Convert between camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE, Title Case, and more with one click.

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Text Diff Viewer

An online tool to compare two texts and highlight the differences (diff). Supports split view and unified view.

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Fullscreen Text

A simple large screen text display tool supporting custom background color, text color, and font size. Suitable for use as a teleprompter, temporary billboard, or large screen display.

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JSON Formatter

Format, compress and validate JSON data

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JSON to Table

Free online JSON to Table converter tool. Convert JSON arrays to HTML tables and export to CSV/Excel files. Runs locally to protect your data privacy.

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LaTeX Editor

Free online LaTeX formula editor with real-time preview, symbol palette, formula templates, and PNG export.

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Markdown Preview

Real-time Markdown text rendering preview

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Random Username Generator

Free online random username generator supporting Chinese and English with multiple styles.

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Unicode Converter

Free online Unicode converter tool. Convert text to Unicode and Unicode to text. Supports \\uXXXX, &#xXXXX;, and &#XXXX; formats. Runs locally in your browser for privacy.

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URL Encoder/Decoder

Online URL encode and decode tool.

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Word Cloud Generator

Free online word cloud generator for multilingual text (Chinese/English/Japanese). Analyze word frequency and export as PNG. Runs locally for privacy.

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Word Counter

Online word counting tool to calculate characters, words, and lines.

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XML Formatter

Online XML formatter, minifier, and XML to JSON converter with tag sorting and syntax highlighting.

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YAML ↔ JSON Converter

Convert between YAML and JSON formats online

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Image Tools

Emoji Icon Generator

Free online Emoji icon generator. Convert any Emoji to PNG icons in multiple sizes and SVG format. Download as a ZIP package. Perfect for favicons and app icons.

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Image EXIF Viewer

Free online EXIF viewer. Drag or select images to parse camera model, shutter speed, aperture, ISO, focal length, shooting time, and GPS. All parsing runs locally in your browser.

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Favicon Generator

Generate multi-size favicons from an image, supporting 16x16 to 512x512

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Image Base64 Converter

Online Image to Base64 and Base64 to Image converter tool

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Image Compressor & Converter

Compress images to JPEG/PNG/WebP with quality and size settings

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Image Crop

Crop images online with free crop or fixed aspect ratios

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Image Merge

Merge multiple images horizontally or vertically into one, with customizable gap and background color

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Image Steganography

Hide text messages inside image pixels. Supports batch processing, runs locally in browser for privacy.

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Image to ICO

Online image to ICO converter. Supports turning PNG/JPG into ICO with multiple custom sizes (16x16 - 256x256).

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Image to SVG Converter

Free online image to SVG converter, converts JPG/PNG bitmaps to SVG vector graphics. Supports color count and blur adjustment, processes locally in browser.

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Image Watermark

Add text watermark to your images easily. Customize position, color, size, and opacity.

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OG Image Generator

Generate beautiful Open Graph (OG) images online for blog posts and social media share cards.

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Image Background Remover

Free online tool to remove white background from images and convert to transparent PNG. Supports threshold adjustment, processes locally in browser for privacy.

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Vintage Photo Maker

Free online vintage photo filter. Convert any photo to retro style with one click. Supports 1920s silent film, 1960s film, 1980s faded styles. Adjust sepia, grain, scratches, and vignette effects.

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Developer Tools

Basic Auth Generator

Free online HTTP Basic Authentication header generator

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Chmod Calculator

An online tool to calculate Linux file permissions (rwx) in both octal (755) and symbolic (-rwxr-xr-x) formats.

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Color Converter

Convert between HEX, RGB, and HSL color formats

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CSV Editor Online

Simple CSV editing and visualization tool, supports online editing, data visualization and export functions

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Docker Generator

Free online Docker command generator. Quickly generate docker run, exec, logs, build, compose commands. Supports port mapping, volume mounting, environment variables.

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DOT Graph Renderer

Free online DOT graph rendering tool powered by Graphviz, renders DOT language graphs in real time.

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File Hash Calculator

Calculate MD5, SHA-1, SHA-256, SHA-512 hash of files online, supports large files

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Headers Analyzer

Fetch website HTTP response headers, analyze security configurations (HSTS, CSP), and detect information leakage risks.

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Mock API (JSON)

Edit JSON online and generate a permanent API link for frontend development and debugging.

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JWT Decoder

Online JWT (JSON Web Token) decoder tool

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Kubectl Generator

Quickly generate common Kubernetes (kubectl) management commands.

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Lorem Ipsum Generator

Generate Lorem Ipsum placeholder text online.

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Social Preview

Extract Meta tags, Open Graph info, and Twitter Cards from webpages, and preview how they look on Google, Facebook, and Twitter.

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Password Generator

Free online random password generator with customizable length and character types.

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Regex Tester

Online regex testing and debugging tool

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Text Encrypt & Share

Encrypt text with AES-256 and generate temporary share links for secure transmission

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UUID Generator

Generate standard UUID/GUID unique identifiers

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Network Tools

Browser Fingerprint

View your browser fingerprint information online

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CIDR Calculator

An online tool to calculate CIDR, subnet mask, broadcast address, and IP range from an IP address and mask bits.

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DNS Lookup

Check DNS records (A, MX, NS, etc.) and Whois information for any domain

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IP Lookup

Look up your IP address and geolocation information online

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Iptables Generator

Quickly generate common iptables commands for firewall management.

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Website Status

Check website accessibility, HTTP status codes, response time, and SSL certificate status.

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Webhook Tester

Generate a unique URL to test and inspect webhooks and HTTP requests.

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Date & Time

Cron Expression Tool

Free online Cron expression parser with visual builder, expression validation, and execution time preview. Easily create scheduled tasks.

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Timestamp Converter

Convert between timestamp and datetime

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Timezone Converter

Free online timezone converter. Parse time strings with timezone offset and convert to multiple timezones instantly. Supports ISO 8601 and various formats.

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Business Tools

Encrypted QR Code

Free online encrypted QR code generator. Use AES-256 encryption to protect text content and generate QR codes that require a password to view. Runs entirely in your browser for privacy.

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Invoice Calculator

Quickly calculate invoice amounts with tax and discount support

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Loan APR Calculator

Calculate the real Annual Percentage Rate (APR/IRR) of loans with flat rates or fees. Reveal the hidden cost of borrowing.

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Number to RMB

Convert numbers to Chinese RMB uppercase

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QR Code Decoder

Upload an image to decode QR codes locally in your browser

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QR Code Generator

Online QR Code generator tool

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Online Raffle (Drag Photos)

Drag student photos to start a raffle; file name is the student's name

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Cryptography

Atbash Cipher

Free online Atbash cipher tool. Reverses the alphabet (A↔Z, B↔Y). An ancient Hebrew cipher where encoding equals decoding.

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Bacon Cipher

Free online Bacon cipher encoder and decoder. Encodes letters as 5-bit A/B binary sequences. Invented by Francis Bacon for steganography.

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Caesar Cipher

Free online Caesar cipher encoder and decoder. Shift letters by a custom offset (1-25). Classic substitution cipher tool, runs locally to protect your privacy.

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Morse Code

Free online Morse code translator. Convert text to Morse code and back, with audio playback. Supports letters, numbers, and punctuation.

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Pigpen Cipher

Free online Pigpen cipher (Masonic cipher) generator. Converts English text into geometric symbols. Copy as image, runs locally.

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Rail Fence Cipher

Free online Rail Fence cipher encoder and decoder. Classic transposition cipher with configurable rails (2-10). Runs locally to protect your privacy.

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ROT13

Free online ROT13 encoder and decoder. Shifts letters by 13 positions — encoding equals decoding. Commonly used to hide spoilers and puzzle answers.

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Vigenère Cipher

Free online Vigenère cipher encoder and decoder. Polyalphabetic substitution cipher with a custom key. Once called "the indecipherable cipher."

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PDF Tools

Image to PDF

Convert images to PDF online for free. Support batch conversion, custom page size and orientation. Process locally to protect privacy.

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PDF Merge

Merge multiple PDF files into one for free online. Support reordering. Process locally to protect privacy.

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PDF to HTML

Free online PDF to HTML converter. Convert PDF documents to editable HTML web pages while preserving original layout and styles. Supports text selection and copying.

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Fun Tools

YES/NO Wheel

Free online YES/NO decision wheel with beautiful spinning animation. Let the wheel of fortune decide for you!

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