PNG to JPG/JPEG — Free Online Image Converter
Convert PNG to JPG/JPEG online for free. Private, client-side — no upload required. Fast batch converter.
About PNG to JPG/JPEG
PNG keeps every pixel with alpha support, which makes files large. JPG encodes the same picture with lossy compression and no alpha channel, so photos shrink while transparency is lost. Flatten transparent areas onto a white or matching background before converting, since JPG cannot store alpha. Set the quality slider near 85 for sharing, higher for prints. Text and line art soften under quantization, so keep the PNG master for graphics and export a fresh copy whenever settings change.
Why convert PNG to JPG/JPEG?
- 采用 JPG/JPEG 的 lossy 压缩，文件更小。
- 在支持的情况下保留 质量。
- 免费、私密、无需上传--在浏览器中运行。
PNG vs JPG/JPEG
| 动画 | 否 | 否 |
|---|---|---|
| 透明度 | 是 | 否 |
| 压缩 | lossless | lossy |
| 典型用途 | PNG 以无损方式存储图像，并支持透明度。 | JPG 与 JPEG 是同一编解码器，只是采用 DOS 时代命名的三位扩展名。 |
When not to convert PNG to JPG/JPEG
- Skip JPG/JPEG for archival masters: lossy compression discards detail, so keep the PNG original.
- Flatten transparency first: JPG/JPEG has no alpha channel, so composite PNG over a background color.
Limits
Starting point: PNG - Lossless graphics with transparency support. Lossless quality means larger files than JPEG. No transparency support, so alpha channels are dropped. Set the quality slider near 80-90 for JPG/JPEG photos from PNG, and keep dimensions matched to the source.
How conversion works
Conversion runs entirely in your browser with the WASM image engine. Files never leave your device.