Encrypto

If you share a sensitive document with a collaborator over email, there’s always the possibility a snoop could intercept it and nab a copy. Even passing the document on a USB drive left in a dead drop doesn’t eliminate all risks. What you need to do is encrypt that data before sharing. That way, anyone who hacks or steals it will get nothing useful. From MacPaw, the Kyiv-based publisher of CleanMyMac, Encrypto makes this kind of encryption extremely easy. As a bonus, it works under both macOS and Windows. Best of all, it's free. That said, AxCrypt Premium also makes sharing encrypted files simple, in a more high-tech fashion that uses public key cryptography under the hood. And Folder Lock offers a wealth of different ways to encrypt and share your files. These two are our Editors’ Choice winners for encryptions products, but you need to pay to use them.

What Is Encryption?

In the classic movie 2001: A Space Odyssey, the villainous rogue AI bears the name HAL-9000. A popular fan theory holds that Stanley Kubrick chose the name HAL because, with each letter shifted to the next, it became IBM. If true, this would be a simple example of a Caesar cipher, though Julius Caesar reportedly preferred to shift three letters before rather than one letter after. Breaking that kind of cipher is a simple matter of analyzing letter frequencies, but it provides a modicum of privacy.

Explaining modern encryption algorithms to Caesar wouldn’t be easy. Their output bears no visible relationship to the data that went in, and cracking a modern encryption algorithm would take an infeasibly long time. The US Government's official encryption algorithm is Advanced Encryption Standard (AES). With a 448-bit key as opposed to AES's 256 bits, Bruce Schneier's Blowfish algorithm would be an even tougher nut to crack.

Encryption systems that use the same key or password to encrypt and decrypt data are called symmetric; AES and Blowfish are examples. If you share a file, you must find a secure and separate way to share the key as well. Public key infrastructure (PKI) cryptography avoids the danger of having that key stolen or exposed. In this system, if I want to send you a file, I look up your public key and encrypt the file with it. You use your private key to decrypt the file. Conversely, if I want to sign a document to prove it comes from me and hasn't been modified, I encrypt it with my private key. The fact that you can decrypt it with the public key proves it came from me and nobody else.

Getting Started With Encrypto

I noticed that the installer for Encrypt states it’s compatible with Windows XP, 7, and 8, suggesting this app hasn’t changed in a long while. For an antivirus tool, that would be a worry, as such tools need to keep up with changes in the malware landscape. But it’s quite common for encryption utilities to go many years without needing any change.

A series of welcome screens points out that Encrypto uses AES-256, that you must remember your encryption passwords or else lose file access, and that it works on Windows or macOS. That last feature is uncommon. EncryptionSafe runs strictly on Windows, as do quite a few others.

Simple Encryption

Encrypting a file or folder with Encrypto is a snap. Drop the item onto the app’s tiny window and enter a password and password hint. Choose where to save the encrypted file, and you’re done. If the file is big enough that encryption takes more than a few seconds, you see a lively animation as Encrypto does its job.

I did find Encrypto’s estimate of time to completion a bit wonky. When I dropped in a folder with 50 files occupying 130MB, it initially just said, “It will take a while.” As it chugged through the job, it estimated anywhere from one to nine minutes left, rapidly shifting between numbers. In the end, it finished in about a minute.

In theory, each file’s password hint will be sufficient to remind you (and nobody else) of the password itself. In practice, it’s easy to forget. What did I mean by the hint “I sat belonely down a tree”? I’d strongly advise storing the filename and password as a secure note in your password manager.

Simple Decryption

Encrypto’s output files have the extension .crypto and the file type Encrypto Container. Launch one or drop it on the Encrypto window to start the decryption process.

Where AxCrypt and EncryptionSafe use a single master password, Encrypto can have a different password for every encrypted container. Presuming you came up with the correct one, you’ve launched the decryption process, with its progress animation. As with encryption, you must decide where to save the resulting file. But that’s all there is to it.

Secure Sharing With Encrypto

With some encryption tools, secure sharing is baked right into the app. When you securely share a file with another user of NordLocker, for example, the recipient gets an email and an in-app notification to accept the file. AxCrypt uses a similar system, though under the hood it relies on PKI technology. Both offer a free version so the recipient can decrypt your shared files without coughing up cash.

Folder Lock, Cryptainer Personal, and Secure IT take a different approach. With these tools, you can turn your encrypted file into a self-decrypting executable. The recipient just runs it and supplies the password to gain access. Of course, you must transmit the password separately, perhaps via a secure messaging utility.

Encrypto doesn’t have any built-in sharing features, but sharing encrypted files is easy enough. You transfer the file using the method of your choice, whether that’s a simple email, a shared online space, or a USB drive. And you send the password by a different channel. The recipient needs Encrypto to open the file, but since it’s free, that’s no big deal. And as noted, Encrypto works on either Windows or macOS.

Unprotected Originals

When you encrypt a document, protecting the plaintext original is essential, and deleting it may not be enough protection. Even if you bypass the Recycle Bin, forensic software can recover the data sectors corresponding to deleted files. If your encrypted data is sufficiently sensitive, you need a tool to completely wipe out the original, so thoroughly that recovery software can’t bring it back.

AxCrypt, FolderLock, and Secure IT are among those encryption utilities that include a secure deletion shredder component for this purpose. Advanced Encryption Package lets techies choose from a confusing array of deletion algorithms, some of them approved by various governments. CryptoForge keeps things simple by overwriting the existing file as part of the encryption process, so there’s nothing left for forensic software to analyze. EncryptionSafe will do the same starting with its next update, which is due by the end of August.

As for Encrypto, it makes no provision at all for securely deleting plaintext originals. If you encrypted a file to share it securely, that’s not a big deal. But if the point was to encrypt it against snoops, well, Encrypto comes up short. At the very least, you should delete the original while holding Shift, to bypass the Recycle Bin. Or empty the Bin after deletion.

What’s Not in Encrypto?

When a single master password opens an encrypted container, as with Steganos Safe, NordLocker, and others, that password is supremely important. If you forget it, you lose access to your files. If a spy or snoop gets it, they can unlock your digital safe. That’s where multi-factor authentication (MFA) comes into play. With MFA, accessing your data requires at least two factors, something you know (like a password), something you have (like an authenticator app), or something you are (like a fingerprint).

Steganos Safe and NordLocker offer MFA using Google Authenticator or a compatible authenticator app. CryptoExpert and Advanced Encryption Package can configure a USB key to act as a physical authenticator. NordLocker also supports authentication using any FIDO-compatible security key. As for EncryptionSafe, it doesn’t offer MFA.

Encrypto also lacks support for MFA, but given its emphasis on sharing encrypted files, that makes sense. As noted, each encrypted file or folder has its own password. Adding MFA separately for each encrypted item would be a bit crazy. And the recipient of a file shared in this way wouldn’t be able to unlock it, because they don’t have your fingerprint or your authentication app.

Protect Your Shared Files

Encrypto makes prepping files for secure sharing about as simple as it can be. Drop in files for encryption, share the result any way you choose, and transmit the password separately. Done! It’s not the best choice for local encrypted file storage, given that each file or folder needs its own password and that there’s no provision for securely deleting originals. But it’s free, and it does its one task very well.

If you’d prefer a Swiss Army knife of encryption to a one-trick app, Folder Lock may be a better choice. It can create encrypted storage containers, turn files into self-decrypting executables, securely shred plaintext originals, and much more. AxCrypt Premium also includes file shredding, and it handles secure file sharing internally, all while secretly relying on top-shelf encryption technology. These two are our Editors’ Choice winners for encryption utilities, but unlike Encrypto, they aren't free.