电子邮件服务器会拒收超过 25MB 的附件，而且大照片会让收件人感到烦恼。发送前压缩您的图片，让它们快速到达并轻松放入收件箱。
此工具在您的浏览器中本地压缩图片 — 不会上传任何内容。
如何使用此工具
添加图片
拖放您的照片，或从您的文件中选择。
目标质量
JPG 已默认选中。70–80 的质量能让照片看起来很棒，同时大幅减小体积。
检查最终大小
目标为每张照片低于 1MB — 对电子邮件来说足够，也远低于服务商的限制。
下载并添加附件
下载您压缩后的图片，并将其附加到电子邮件中。
本节目前仅提供英文版本。
What email actually needs
Email is the most size-constrained place an image goes. Most providers cap attachments at 20–25 MB, and many corporate mail systems are stricter — some reject anything over 10 MB, and a few over 5 MB. Base64 encoding used by mail transfer adds roughly 33% on top of the file size, so a 20 MB image becomes about 27 MB on the wire.
The practical target is a few hundred kilobytes per image, which keeps a message with several attachments comfortably small and courteous to the recipient’s inbox.
Sensible targets
| What you are sending | Target size | Notes |
|---|---|---|
| A photo to a friend or colleague | 200–500 KB | Plenty for screen viewing |
| Several photos in one message | Under 2 MB total | Compress each, or use a link |
| A document scan or receipt | Under 500 KB | Keep text legible; do not over-compress |
| A screenshot for a bug report | Under 300 KB | PNG or lossless WebP; text stays sharp |
| A print-quality image someone will print | Do not email it | Send a link or a transfer service instead |
Resize first, compress second
A modern phone photo is often 4000 pixels wide and 4 MB. Nobody needs that in an email. Resizing to 1600 pixels on the long edge — which still fills a laptop screen — cuts the data by roughly 85% before any compression setting is touched. Doing the resize first means the compressor has far less work to do and the result looks better.
Keeping scans readable
Compressing a scan of a document is the one case where over-compression really bites: JPEG artefacts land on the letter edges and small print becomes smeared. Use PNG or lossless WebP for anything text-heavy, and if it is still too large, reduce the resolution to around 150 DPI rather than crushing the quality.
常见问题
用于电子邮件的图片应该多大？
每张图片低于 1MB 是理想的选择。大多数服务商将附件总大小限制在 25MB，因此更小的文件意味着您可以发送更多照片。
JPG 最适合电子邮件吗？
JPG 是电子邮件中照片兼容性最好的格式。某些电子邮件客户端会移除或阻止其他格式。
这个工具会上传我的照片吗？
不会 — 压缩完全在您的浏览器中完成。