PDF 合并工具
在本地安全合并多个 PDF 文件为一个文档,并自由整理页面顺序。
在 PNG、JPEG 和 WebP 之间自由转换图片格式,支持画质调节。
支持 PNG、JPEG 和 WebP 互转 · 减小文件体积 · 批量快速处理
PNG, JPEG, WebP, GIF and BMP · no size limit · no sign-up
The aspect ratio is always kept. Images are only scaled down, never up.
Lower means a smaller file. 75–85% usually looks identical to the original.
Fills see-through areas. Only used for JPEG, which cannot store transparency.
Rotates photos upright using the orientation recorded by your camera or phone.
快速在 PNG、JPEG 和 WebP 格式之间互相转换,并通过画质滑块自由控制文件大小。您的照片绝不上传至服务器 – 纯在浏览器中安全完成。
Four steps, no account, nothing uploaded.
将图片文件拖入操作区域,或点击按钮从您的设备中选取图片。
透明背景选 PNG,普通照片选 JPEG,追求极小体积选 WebP。
使用画质滑块在清晰度与文件体积之间自由调整设定。
点击“全部转换”,然后将优化后的图片保存到您的电脑或手机上。
Built so your files never have to trust a server.
浏览器直接在您本地设备上完成解码与重编码,没有任何数据经由网络传输。
拖动画质滑块,在清晰的视觉观感与精简的文件体积之间找到最佳平衡。
一次性添加多张图片,只需轻点一下即可全部快速转换完毕。
无需注册账号、不加水印,对原始图片大小没有任何人为限制。
Everything people ask about the Image Converter.
不会。转换过程 100% 通过 HTML5 Canvas API 在您的浏览器本地完成。
添加您的 PNG 文件,选择 JPEG 作为输出格式,调整画质(推荐 85%),然后点击转换即可。
PNG 采用无损压缩算法。若想显著缩小体积,强烈建议选择现代的 WebP 或 JPEG 格式。
针对 JPEG 和 WebP,它调节有损压缩比例,以平衡视觉清晰度与文件存储空间。
本站没有设立任何人为限制。唯一的上限取决于您设备当前的可用内存(RAM)。
PNG 和 WebP 格式会保留透明度。JPEG 格式不支持透明度,会将透明区域填充为纯色。
原生支持 HEIC 的浏览器(如 Apple 设备上的 Safari)可以直接打开并转换 HEIC 图像。
More free utilities that run entirely in your browser.
在本地安全合并多个 PDF 文件为一个文档,并自由整理页面顺序。
轻松将文本与文件编解码为标准 Base64 及 URL-Safe 格式。
实时统计文本字数与字符,附带可读性得分和关键词密度深度分析。
探索适用于所有现代格式的免费、私密浏览器端图像转换工具。
Lossless bitmap image format supporting full alpha transparency. Ideal for web graphics, logos, icons, and illustrations.
Widely compatible lossy image format designed for photographs and complex real-world scenes with small file sizes.
Modern image format developed by Google providing superior lossless and lossy compression with transparency for web performance.
XML-based vector graphic format that scales infinitely to any resolution without pixelation or quality loss.
Bitmap image format supporting up to 256 indexed colors and frame-based animations.
Standard icon file format used for browser favicons, desktop application shortcuts, and system icons.
Uncompressed raster graphics format storing exact pixel data without compression artifacts.
Advanced media container used by Apple iOS and macOS devices storing high-quality photos at half the file size of JPEG.
Professional high-resolution format widely used in desktop publishing, photography, medical imaging, and printing.
Layered graphic format created by Adobe Photoshop containing composite image bitmaps, masks, and layers.
PostScript-based vector and raster format used in professional prepress and graphic design illustration.
Raster format originally designed for Truevision video cards, widely utilized in 3D gaming textures and animation rendering.
Standardized variation of JPEG containing minimal metadata and JPEG compression blocks.