压缩 JPG — 免费在线，无需上传
Drop a JPG or JPEG photo into PicBrewery and download a smaller file re-encoded with MozJPEG — no account, no watermark, no upload. Everything runs in WebAssembly inside your browser.
See the JPEG section on the formats hub for codec details.
如何压缩 JPG
- Open PicBrewery.
- Drag and drop your
.jpgor.jpegfile (or several) onto the drop zone. - PicBrewery decodes the JPEG and re-encodes JPEG, PNG, WebP and AVIF in parallel. Compare byte sizes in the results row — the JPEG column is your re-compressed JPG.
- Click the download icon on the JPEG cell, or use Download all as ZIP for batches.
PicBrewery 中的 JPG 压缩原理
PicBrewery does not resize or crop images. Compression means re-encoding the same pixels with a modern JPEG encoder (MozJPEG) at tuned quality settings, plus stripping EXIF, ICC and XMP metadata to save bytes.
For photos already saved at quality 85–90, a fresh MozJPEG pass at quality 75–80 often yields 10–30% smaller files with no visible difference. Gains are smaller if the source was already heavily optimized.
保留 JPG vs 转为 WebP/AVIF
需要最大兼容性（邮件、CMS、印刷）时保留 JPG。Web 交付请比较 WebP 与 AVIF 列。JPG 转 WebP或压缩 WebP。
常见问题
压缩 JPG 会降低画质吗？
Re-encoding JPEG is lossy — each save can add artifacts. PicBrewery defaults to quality settings tuned for size at matching perceived quality. Use the quality slider under Advanced settings if you need a higher bitrate.
JPG 会小多少？
Typical camera JPEGs shrink 10–30% after MozJPEG re-encode and metadata stripping. Drop your file into PicBrewery to see exact byte counts for every output format side by side.
EXIF 和 GPS 数据会保留吗？
No. PicBrewery strips EXIF, ICC and XMP on re-encode to keep files small. Keep the original if you need metadata.
可以批量压缩 JPG 吗？
Yes — up to 20 files per batch, 20 MB each, with Download all as ZIP.
PicBrewery 会改变图片尺寸吗？
No. Compression here means re-encoding only — pixel dimensions stay the same.