在线免费压缩 JPG 图片。无论是通过电子邮件发送照片、上传到网站还是存储图片，更小的 JPG 都能节省时间和带宽。
此工具完全在您的浏览器中运行，因此您的图片绝不会离开您的设备。
如何使用此工具
添加 JPG
将您的 JPG 拖放到工具上，或选择文件。
设置质量
JPG 已默认选中。70–80% 的质量可以消除大多数可见瑕疵，同时显著减小文件大小。
对比并下载
预览效果，然后下载您压缩后的 JPG。
本节目前仅提供英文版本。
What you are actually trading away
A JPEG has already been compressed once. Compressing it again re-encodes an image that has already lost detail, so the artefacts compound: what looked clean at quality 85 will look noticeably softer after a second pass at 70. Each additional pass costs more than the last.
This is why the quality slider on a re-compression tool behaves differently from the one in a camera or an editor. In an editor you are encoding from original data. Here you are encoding a copy of a copy.
Choosing a quality setting
| Setting | Typical use | What it costs |
|---|---|---|
| 85–95 | Archive, print preparation, images that will be edited again | Barely any saving; near-original size |
| 70–85 | Web delivery, hero images, photographs viewed on screen | Slight softening, generally invisible at normal size |
| 50–70 | Thumbnails, previews, email attachments | Visible artefacts on close inspection |
| Below 50 | Only when size is the overriding constraint | Blocking and banding that most people will notice |
Getting a better result
- Compress once, from the original, rather than repeatedly from the JPEG.
- Resize before compressing — fewer pixels always beats a harder encoder setting.
- Keep the original file. Re-compression is one-way.
- If you will compress again later, start from the original then too.
常见问题
JPG 可以压缩多少？
通常可节省 30–70%，具体取决于源图片和您选择的质量等级。
压缩 JPG 会降低质量吗？
JPG 压缩是有损的，但在质量 70–80 时，用于网页通常看不出差别。
有任何限制吗？
没有限制，无需账号，没有水印。您想压缩多少图片都可以。