为什么要把 PNG 转为 JPG？
PNG is a lossless format, which is great for screenshots, logos and graphics with sharp edges — but the files are often much larger than they need to be. JPG uses smart compression that is designed for photographs and realistic images, typically shrinking a photo to a fraction of its PNG size with barely visible difference. If you are emailing photos, uploading to a website, or submitting images to a form with a file-size limit, converting PNG to JPG is usually the fastest fix.
Common situations where PNG to JPG conversion helps: a screenshot saved as PNG that is too large to attach to an email, product photos for an online store that slow down page loading, or images for a job application portal that rejects files over a size limit. JPG is also the most universally accepted image format — virtually every website, app and device opens JPG without complaint.
如何将 PNG 转为 JPG
1. Drop your PNG images into the box above, or click to choose files from your device. You can convert several images at once.
2. Make sure JPG is selected as the output format (it is the default).
3. Press 转换. Each image is re-encoded at high quality (92%) and downloaded automatically — a single image downloads directly, multiple images are bundled into a ZIP file.
Note: JPG does not support transparency. If your PNG has a transparent background, it will be filled with white during conversion. For logos or graphics where transparency matters, keep the PNG or use the general image converter to pick a different format.
PNG 和 JPG 该用哪个？
Use PNG for screenshots, logos, icons, diagrams and any image with text or sharp lines — PNG keeps every pixel exact. Use JPG for photographs, camera pictures and realistic images where a tiny quality trade-off buys you a dramatically smaller file. A good rule of thumb: if the image came from a camera, JPG; if it came from a screen capture or a design tool, PNG.
Converting from PNG to JPG is a one-way street for quality: once compression discards detail, converting back to PNG will not restore it. Always keep your original PNG if you might need the full-quality version later.
常见问题
PNG 转 JPG 会降低画质吗？
Slightly. JPG is a lossy format, so some fine detail is discarded. At the high quality setting this tool uses (92%), the difference is barely visible for photos. For screenshots with text or sharp graphics, you may notice softening — keep those as PNG.
PNG 转 JPG 支持透明背景吗？
不支持。JPG 没有透明通道，透明区域会变成白色。 If you need to keep transparency, stay with PNG or convert to WebP.
有文件大小限制吗？
No artificial limit. Conversion happens in your browser, so the practical limit is your device's memory. Very large batches may be slower on older phones.
我的图片会被上传吗？
不会。转换完全在您的设备上通过 JavaScript 运行，文件不会离开浏览器。
可以一次转换多张 PNG 吗？
Yes. Select several files and they will all be converted; if there is more than one, you get a single ZIP download.
JPG 和 JPEG 有什么区别？
没有区别——它们是同一种格式。 JPG is just the three-letter file extension from the days when extensions were limited to three characters.