指南与教程
关于数字签名和文档工作流程的实用指南。
如何在线创建数字签名（免费）
绘制、自定义和下载您的数字签名的分步指南——无需创建账户或上传任何内容。
如何在不上传的情况下在线签署PDF
了解如何完全在浏览器中向PDF文档添加签名，保持文件完全私密。
如何在Word文档中添加签名
将手写风格签名图像插入Microsoft Word、Google文档的实用指南。
电子签名与数字签名：有什么区别？
我们解释了主要区别、法律含义以及日常文件真正需要哪种。
Developer Tools Guides
How-to guides for the browser-based developer tools — formatting, encoding, hashing, and more.
How to Format JSON Online (Free)
Format, validate, and beautify minified JSON in one click. Includes validation errors and copy/download.
How to Decode a JWT Token Online
Decode a JWT to read its header, payload claims, and expiry timestamp. Browser-only — your token stays private.
How to Generate a UUID Online (Free)
Generate cryptographically secure UUID v4 identifiers in bulk using your browser's Web Crypto API.
How to Encode and Decode Base64
Convert text to Base64 or decode Base64 strings back to plain text. Includes URL-safe Base64 explained.
How to Generate a SHA-256 Hash Online
Generate SHA-256, SHA-512, SHA-1, and MD5 hashes simultaneously. Includes guidance on which algorithm to use.
How to Format SQL Queries Online
Format and beautify SQL with dialect support for MySQL, PostgreSQL, T-SQL, SQLite, and more.
How to Compare Two Text Files Online
Find differences between two texts with color-coded diff output. Added, removed, and unchanged lines.
How to Test Regular Expressions Online
Write, debug, and validate regex patterns with live match highlighting and capture group display.
How to Convert Color Codes (HEX RGB HSL)
Convert between HEX, RGB, HSL, and CMYK color formats instantly with a live swatch.
How to Create a Favicon for Free
Generate 16×16, 32×32, 48×48, and 64×64 PNG favicons from any logo using the Canvas API.
Graphics Tools Guides
How-to guides for resizing, compressing, and creating visual content — entirely in your browser.
How to Resize an Image Online (Free)
Set exact pixel dimensions or scale by percentage with aspect ratio lock. Browser-based, no upload required.
How to Compress an Image Online (Free)
Reduce image file size with a quality slider. Live before/after size comparison. No server upload.
How to Convert Image Format Online
Convert between PNG, JPEG, WebP, and BMP in your browser. Includes guidance on which format to use.
How to Add a Watermark to an Image
Add text or image (logo) watermarks with position grid and opacity control. Download PNG instantly.
How to Optimize SVG Files Online
Remove editor metadata, comments, and redundant attributes. Achieve 30–70% size reduction.
How to Make a Bar Chart Online (Free)
Enter labels and values, customise colours and axis labels, download PNG. Browser-based with Chart.js.