All Converter Pro
在线 JPG 转 PNG
在线免费将 JPG 转换为 PNG。PNG 是无损的,因此图片在进一步编辑时不会降质。即时转换,无需注册,无水印。
关于此 JPG 转 PNG 工具
This converter turns a JPG (JPEG) photo into a PNG file. The practical reason to do this: PNG is a lossless format. A JPG loses a little quality every time it is edited and re-saved, while a PNG can be opened, edited and saved repeatedly with zero degradation - which is why designers convert to PNG before retouching, annotating or compositing an image. PNG is also the format many tools, CMSs and print workflows require for logos, screenshots and graphics with text. Note the honest trade-off: converting cannot restore detail the JPG compression already discarded, and PNG files are usually larger than the source JPG because nothing is being thrown away.
如何使用 JPG 转 PNG
- 打开工具并添加您的文件、文字或数值。
- 检查可用选项,例如页面范围、输出格式、质量、密码或语言。
- 开始处理,并在完成前保持浏览器窗口打开。
- 下载结果,如有需要可继续使用相关工具。
实用提示
- 对于扫描的 PDF,支持 OCR 的工具会尽可能自动运行文字识别。
- 对于大文件,在通过邮件分享或上传到门户网站之前,请使用压缩工具。
- 为获得最佳效果,请上传扩展名正确的干净文件,避免使用损坏的文档。
JPG vs. PNG: which format for what
JPG is best for photographs going to the web or email: small files, and the quality loss is invisible for one-time viewing.
PNG is best for screenshots, logos, charts, text-heavy images, and any image that will be edited again - its lossless compression keeps sharp edges crisp.
If file size matters more than anything (page speed, email limits), consider WebP via the WebP Converter: it beats both JPG and PNG on size for most images.
常见问题
Why convert JPG to PNG at all?
PNG is lossless, so the image survives repeated editing and saving without degrading. Convert before retouching or annotating a JPG, or when a website, tool or print shop specifically requires PNG.
Will converting to PNG improve my image quality?
No. Conversion preserves the image exactly as it is but cannot recover detail that JPG compression already removed. It prevents further quality loss; it does not undo past loss.
Will the PNG be transparent?
No. JPG has no transparency, so there is nothing to carry over - the PNG will have the same solid background as the JPG. To make the background transparent, use the Background Remover tool instead.
Why is my PNG file larger than the JPG?
JPG achieves small files by discarding detail; PNG keeps everything, so photos in particular grow in size. That is the normal cost of a lossless format.
Can I convert multiple JPG files?
转换 them one at a time - each conversion takes a few seconds and the download appears on the same page.
转换器是免费且私密的吗?
Yes. Free with no signup or watermark, and uploads are stored only temporarily under random names before automatic cleanup.