把两张图放在一起看：拖动分割线左右对照、并排同步缩放、半透明叠加，或者直接看逐像素差值图。图片不上传，对比与导出都在浏览器本地完成。
How to use: 1) Import A (the original) and B (the one to compare). 2) Choose a mode: slider, side by side, translucent overlay, or per-pixel difference. 3) Drag the divider or adjust the gain, then export the composite or the difference image.
两张图尺寸不一样怎么办？
默认按较大尺寸对齐居中，不拉伸；取消勾选「自动对齐尺寸」则把 B 拉伸到 A 的尺寸。
差值图为什么会过亮或过暗？
差值图显示的是 |A−B| 乘以增益。调「差值增益」可以放大或压暗差异，超出上限的差异会被截断。
What if the two images differ in size?
By default they are centred on the larger canvas without stretching; untick Auto-align to stretch B to A's size instead.
Why does the difference image look too bright or too dark?
It shows |A−B| multiplied by the gain slider; extreme differences clamp at the maximum.
全程在浏览器本地处理，文件不上传；如需不限次数使用，VIP 会员 可解锁全部 29 个工具。