大家好，我是来自法国的 Amir Moradi。我不会中文，下面的内容是借助 AI 翻译成中文的，如有翻译不准确或用词不当的地方，还请大家多多包涵。英文原文附在文末。
软件名称
Cachety
应用平台
Online Service（网页版，电脑以及 iPhone、Android 手机的浏览器都能用）
推荐类型
〖开发者自荐〗
一句简介
直接在浏览器里给身份证等证件加水印，文件全程不上传。
应用简介
租房、求职、开银行账户……总有人要我们提供身份证复印件。可复印件一旦发出去，就不再由自己掌控，可能被拿去做任何事，甚至被冒用身份。在复印件上写明用途、接收方和日期，就能让它很难被挪作他用。
问题在于，大多数在线加水印工具，都要先把你的身份证上传到它们的服务器上才能处理。为了保护最敏感的证件，反而要先把它交出去，我觉得这说不通，于是做了 Cachety。
Cachety 的所有处理都在你自己的浏览器里、在你自己的设备上完成。文件不会发送到任何地方——网站甚至根本没有能接收文件的服务器。这一点不用只听我说，你可以自己验证：打开页面后开启飞行模式，再给文件加水印，照样能用。
使用方法：
- 打开 cachety.com，拖入 PDF 或照片（iPhone 的 HEIC 照片也支持）。
- 输入水印文字，比如"仅供租房申请使用，XX房产，2026年10月11日"，也可以直接选一个现成的模板。
- 预览确认无误后，下载即可。
其他功能：
- 水印沿斜线铺满整页，并直接融进图片里，单纯编辑 PDF 是去不掉的。
- 遮盖：可以涂掉身份证号、银行卡号等信息。内容会被真正删除，而不只是盖上一层。
- 自动去除文件里的隐藏信息，比如元数据和照片的 GPS 位置。
- 可追溯副本：每一份都可以带上日期和唯一编号。
- 可以为每个接收方各生成一份专属版本，一次下载全部。
- 可选给 PDF 加 AES-256 密码。
- 手机上也能用，还能像 App 一样添加到主屏幕。
- 界面支持简体中文、英语、法语、日语、西班牙语、阿拉伯语和波斯语。
完全免费，无需注册，没有广告，并以 AGPL-3.0 协议开源：GitHub - cachety/cachety: Watermark your documents without sending them anywhere ID card, passport, payslip, bank statement: add a watermark in seconds. Your files stay on your device from start to finish. · GitHub
非常欢迎大家提意见，尤其是中文界面里如果有哪里读起来不自然，请一定告诉我。
官方网站
Software name
Cachety
Platform
Online Service (works in any modern browser, on computers and on iPhone and Android phones)
Type
Developer’s own work
One-line summary
Watermark ID cards and other documents right in your browser: the file is never uploaded.
Introduction
Renting a flat, applying for a job, opening a bank account: we keep being asked for a copy of our ID card. Once you send it, that copy is out of your hands, and it can be reused for anything, including identity theft. Writing on the copy what it is for, who it is for and the date makes it much harder to misuse.
The problem is that most online watermark tools first upload your ID card to their servers to do the job. Uploading the most sensitive document you own, in order to protect it, didn’t make sense to me. So I built Cachety.
Cachety does all the work inside your own browser, on your own device. The file is never sent anywhere: there isn’t even a server that could receive it. You don’t have to take my word for it. Open the page, switch on airplane mode, and watermark a document: it still works.
How to use it:
- Open cachety.com and drop in a PDF or a photo (iPhone HEIC photos work too).
- Type the watermark text, for example “For rental application only, XX Real Estate, 11 Oct 2026”, or pick a ready-made template.
- Check the preview, then download.
Other features:
- The watermark is repeated diagonally across the whole page and blended into the image, so it can’t be removed by simply editing the PDF.
- Masking: black out an ID number or a bank card number. The content is really removed, not just covered.
- Hidden information in the file (metadata, the GPS location of photos) is removed automatically.
- Traceable copies: each copy can carry the date and a unique reference.
- One personalised version for each recipient, in a single download.
- Optional AES-256 password on the PDF.
- Works on phones, and can be added to the home screen like an app.
- Interface in Chinese, English, French, Japanese, Spanish, Arabic and Persian.
It’s free, needs no account, has no ads, and is open source under the AGPL-3.0 licence: GitHub - cachety/cachety: Watermark your documents without sending them anywhere ID card, passport, payslip, bank statement: add a watermark in seconds. Your files stay on your device from start to finish. · GitHub
Feedback is very welcome, especially if something in the Chinese interface sounds unnatural.