jKeyCrypt

jKeyCrypt is a small-sized application designed in Java, which gives you the possibility to encrypt and decrypt text using key files.
It doesn't require previous experience with cryptography tools, since it has a pretty straightforward set of options.

Java-based app for encrypting and decrypting text

Installing the text encryptor isn't necessary because it's wrapped in a single .jar file that can be saved anywhere on the computer and launched by just double-clicking it. Otherwise, it can be copied to a removable storage unit and deployed on any machine. Just make sure it's equipped with Java Runtime Environment or it won't work.

Generate key files to encrypt and decrypt text

At startup, jKeyCrypt offers to create a key file, which will be used for encrypting and decrypting text throughout the current session. However, regular files may also be used as keys by just importing them into this app.
The main window of the encryption app has a simple look, where you can enter text you want to encrypt in the first box, click the "Encrypt" button, and view the output with the encrypted text in the second box.

Keep your key files safe to decode information

To decrypt content, simply enter it in the second box, click "Decrypt" and view the original text in the first box. Content can be selected and copied to the Clipboard via the right-click menu or by clicking Ctrl+C. Just make sure the correct key file is opened to be able to perform a successful decryption job.
It's also possible to generate new key files on the spot. The important thing is to keep the key files safe and in your reach or you won't be able to decrypt the text.

Conclusion

All in all, jKeyCrypt offers a simple solution for securing text using key files. However, its interface is unpolished and instructions are unclear for first-time users.