i  Safe Crypt App

The Safe Crypt App allows you to easily encrypt and decrypt files using the AES-256 cipher in GCM mode. This web app works locally in your browser by using JavaScript, so it never sends a bit of your data over the Internet. If you are still worried about snooping, you can even turn off WiFi and mobile data once you have loaded the app's home page. This app is a straightforward way to share sensitive information with others or store confidential documents in the cloud.

The app works on most platforms with Chrome, Opera, Edge, and Vivaldi, except on iPhones and iPads, where you need to use Safari. However, it also works with many other browsers: please check this com­pat­i­bil­i­ty list. The app limits the size of the files to be encrypted to 20 Mbytes or, on most mobile browsers, to 10 Mbytes. The encrypted files are about 1.8 times the size of the original files. The reason for this is that they are text files (JSON with a large Base64 encoded element).

This app is suitable for use on both desktop and mobile devices. It checks the compatibility of your browser and, in most cases, prevents the use of an incompatible browser. It includes network security and integrity checks. A listing of the current source code is always available. To better understand the risks of using this app, check out this reflection.

For an introduction to its use, see the Safe Crypt App guided tour.

The app is compliant with the EU GDPR and with the EU ePrivacy Directive, see the privacy policy.


This app is a derivative work of the Encryption App created by Mark Angelov and published by the TutorialZine* under their own permissive license. The current app employs the browser's native Web Cryptography API* through a slightly modified version of Dan Davis' wrapper aes4js*, licensed under the MIT License (Expat). The app includes hyphenation software by Mathias Nater, licensed under the MIT License (Expat). The app uses the jQuery* library, which is also licensed under the MIT license (Expat). The current author* is responsible for the modified code, and it is licensed under the GNU General Public License Version 2.

Version 1.210503