How Batch Image Conversion Works in Your Browser
Modern browsers support high-performance off-main-thread image processing using Web Workers and OffscreenCanvas. By decoding and re-encoding raster image data locally, you can convert dozens of pictures instantly without uploading sensitive files to any external cloud server.
Supported Formats & Best Use Cases
- WebP: Next-generation image format offering superior lossy and lossless compression. Reduces file size by 25–35% compared to JPEG while preserving visual fidelity. Ideal for web performance and SEO Core Web Vitals.
- JPEG / JPG: Universal lossy compression standard best suited for photographic content and complex imagery where high color depth is required.
- PNG: Lossless compression supporting full alpha transparency. Perfect for logos, interface mockups, icons, and illustrations with sharp geometric boundaries.
Frequently Asked Questions
- 我的图片会被上传到任何服务器吗？
- 完全不会。所有图片转码与 ZIP 打包压缩 100% 在您的本地浏览器内存中利用 Web Worker 和 Canvas 完成，图片从不离开您的设备。
- 单次批量最多可以转换多少张图片？
- 为了防止手机或低内存设备标签页崩溃，单次批处理硬性限制为最多 20 张且总大小不超过 50MB。
- 如何一键打包下载所有转换后的文件？
- 待列表内任务转码完毕后，点击顶部的“打包下载全部 (.zip)”按钮，即可将所有图片快速生成单个压缩包保存。