🗜️ 图片压缩到指定大小（KB）Compress Image to Size (KB)
把照片压缩到指定 KB 以内，例如 20 KB、50 KB、100 KB、200 KB，适合考试报名、社保、签证、简历等网站上传；可同时设置最小大小和像素尺寸（如 295×413），自动寻找最佳画质，批量压缩打包下载，图片不上传。Compress photos to a target size such as 20, 50, 100 or 200 KB for exam, visa and job-application uploads. Optionally set a minimum size and exact pixel dimensions (e.g. 295×413); the best quality that fits is found automatically, with batch ZIP download. Nothing is uploaded.
使用说明与常见问题How-to & FAQ
「图片压缩到指定大小（KB）」是什么？What is the Compress Image to Size (KB)?
把照片压缩到指定 KB 以内，例如 20 KB、50 KB、100 KB、200 KB，适合考试报名、社保、签证、简历等网站上传；可同时设置最小大小和像素尺寸（如 295×413），自动寻找最佳画质，批量压缩打包下载，图片不上传。Compress photos to a target size such as 20, 50, 100 or 200 KB for exam, visa and job-application uploads. Optionally set a minimum size and exact pixel dimensions (e.g. 295×413); the best quality that fits is found automatically, with batch ZIP download. Nothing is uploaded.
如何使用「图片压缩到指定大小（KB）」？How do I use the Compress Image to Size (KB)?
选择或拖入图片，在“目标大小”里填写网站要求的 KB 数（例如 50），如果网站还要求像素尺寸，就选择“指定宽高”并填入宽和高。点“开始压缩”，每张图片会显示压缩后的大小和画质，点下载即可，多张可以“全部下载”。Choose or drop images and enter the required size in KB (e.g. 50). If the site also requires pixel dimensions, pick “Exact size” and enter width and height. Press Compress; each image shows its new size and quality — download one by one or all as ZIP.
为什么压缩后还是超过要求大小？Why is the result still too large?
工具会先降低 JPG 画质，画质降到很低还不够时才会自动缩小像素尺寸。如果你锁定了像素尺寸，而尺寸又很大，可能无法压到很小，请适当减小像素尺寸或放宽大小限制。PNG 会自动转成 JPG 来压缩。The tool lowers JPG quality first and only then scales the image down. If you locked large pixel dimensions, a very small target may be impossible — reduce the dimensions or the target. PNGs are converted to JPG to compress.
网站要求“大于 20 KB 小于 50 KB”怎么办？The site needs “between 20 KB and 50 KB” — how?
在“目标大小”填 50，“最小大小”填 20。如果压缩结果小于 20 KB，工具会自动改用最高画质；仍然偏小时会给出提示，这时把像素尺寸调大一些即可。Enter 50 as the target and 20 as the minimum. If a result is below 20 KB the maximum quality is used; if it is still too small you get a warning — increase the pixel size.
1 KB 是 1000 字节还是 1024 字节？Is 1 KB 1000 or 1024 bytes?
本工具按 1 KB = 1024 字节计算，与 Windows 文件属性显示一致，也更严格，按 1000 字节计算的网站也一定能通过。This tool uses 1 KB = 1024 bytes, matching Windows file properties. It is the stricter definition, so sites that use 1000 bytes accept the result too.
「图片压缩到指定大小（KB）」免费吗？文件会上传吗？Is the Compress Image to Size (KB) free? Are my files uploaded?
「图片压缩到指定大小（KB）」完全免费，无需注册。图片只在你的浏览器里处理，不会上传到任何服务器，关闭页面后不留痕迹。The Compress Image to Size (KB) is free with no sign-up. Images are processed only in your browser, never uploaded to any server, and nothing is kept after you close the page.