JPEG Quality Filter

WordPress recompresses your images at 82% — change it

在你的浏览器里运行。什么都不上传。

Quality

JPEG quality 82

40 — visibly degraded 82 — WP default 100 — no gain, big files

What it does to a flat graphic

A hard edge on a flat colour is the worst case for JPEG. Drag the slider and watch the halo appear around the shapes. This is rendered live in your browser at the exact quality you picked.

Original

Scope

Use a higher quality for large sizes onlyKeeps thumbnails small while protecting the full-size image. This is the setting most sites actually want, and almost no tutorial mentions it is possible.

functions.php

Only affects images uploaded AFTER the filter is active. Existing images keep the quality they were encoded at until you regenerate them. And note the preview above is your browser's JPEG encoder, not your server's — the artefacts are representative, the byte counts are not.

关于JPEG Quality Filter

Every JPEG you upload is re-encoded at quality 82 by default. That is fine for photos and visibly bad for screenshots and flat graphics. This generates the filter to change it, with a live preview of what each quality level costs.

你可能还需要的其他工具

Disable -scaled Images

Stop WordPress silently shrinking your big uploads

FAQ

常见问题

WordPress 默认用的 JPEG 质量是多少？

82。你上传的每一张 JPEG 都会以这个质量被重新编码，WordPress 从它生成的每个衍生尺寸也一样。对照片来说这是个合理的默认值，但对截图、logo 和纯色平面图形来说就明显偏差了——那些有硬边缘，也没有照片噪点来掩盖压缩瑕疵。

我应该把 JPEG 质量设成 100 吗？

不该。大约超过 92 之后，你买到的是文件体积而不是肉眼可见的质量，而 100 可能让文件大三倍，换来的却是没人会注意到的差别。如果你的图片是截图或 UI 图形，88–92 是合理的区间。

改这个能修好我已经上传的图片吗？

不能。这个过滤器只作用于它生效之后处理的图片。已有的图片会一直保持它们被编码时的质量，直到你重新上传，或者用插件、用 “wp media regenerate” 重新生成缩略图。