Why convert JPG to PNG?
JPG is a lossy format: every time a JPG is saved, a little detail is discarded. PNG is lossless, so it preserves every pixel exactly. Converting an existing JPG to PNG will not magically restore lost quality — but it stops further degradation. That matters when you plan to edit an image repeatedly: each JPG re-save degrades it a little more, while PNG re-saves are bit-perfect.
The other big reason is transparency. JPG has no alpha channel, so it cannot have transparent backgrounds. Designers often convert a JPG to PNG as a first step before cutting out a background or compositing the image into a design. PNG is also the right choice for images that will go through more processing — resizing, color correction or text overlays — because you want to start from the cleanest possible source.
How to convert JPG to PNG
1. Drop your JPG or JPEG images into the box above, or click to choose files. Batch conversion is supported.
2. Make sure PNG is selected as the output format.
3. Press 转换. Each image is re-encoded losslessly and downloaded automatically — single images download directly, multiple images come as a ZIP file.
Heads-up: PNG files are usually larger than the JPG you started from, especially for photographs. That is normal — PNG stores every pixel exactly instead of approximating. If your goal is a smaller file, you want PNG to JPG or image compression instead.
When should you keep JPG instead?
If the image is a finished photograph that you will simply view or share, keep the JPG — it is smaller and looks identical. 转为 PNG when you need lossless editing, transparency work, or an archival master copy. For web use, also consider WebP, which offers PNG-like quality at much smaller sizes in modern browsers.
常见问题
JPG 转 PNG 能提升画质吗？
不能。JPG 压缩丢失的细节无法恢复。转为 PNG 只能避免进一步损失。 Converting to PNG only prevents further quality loss on future edits and saves.
为什么 PNG 文件比 JPG 大？
PNG is lossless — it stores every pixel exactly, while JPG approximates. For photographs, PNG files are typically several times larger than the equivalent JPG.
JPG 可以有透明背景吗？
不可以。JPG 不支持透明。 转为 PNG first, then remove the background in an editor to get transparency.
我的图片会被上传到服务器吗？
不会。转换完全在浏览器中进行，文件不会离开您的设备。
可以转换 WebP 或其他格式吗？
Yes — use the general image converter for WebP, AVIF and other format combinations.
转换后的 PNG 在哪都能用吗？
Yes. PNG is one of the most widely supported image formats, readable by every browser, phone and image editor.