Best Zero-Knowledge Cloud Services 2018

obrBy Joseph Gildred — Last Updated: 02 Mar'18 2017-01-30T06:02:18+00:00

When it comes to cloud security for file hosting, private, end-to-end encryption is kind of the gold standard. While actually a hijacked term in cryptography, today it’s common to call this this type of encryption “zero-knowledge.”

Zero-knowledge encryption means only you have control of your cloud encryption keys, so only you can ever decrypt your files into plain text. That means no sketchy government surveillance, no using your private photos for targeted marketing and less chance of a breach compromising your identity.

However, while any zero knowledge is good, some implementations are better than others. During this roundup, we’ll unveil our picks for the best zero-knowledge cloud services available today. Headed by what may actually be the overall best cloud storage service,, this list will help keep your private affairs exactly that.  

Best Zero-Knowledge Cloud Services of 2018

Rank Company
Price Link
1 Winner
$ 4.08 per month 500 GBStorage All Plans
Visit Review
$ 4.99 per month 500 GBStorage All Plans
Visit pCloudpCloud Review
SpiderOak ONE
$ 5.00 per month 100 GBStorage All Plans
Visit SpiderOak ONESpiderOak ONE Review
$ 12.50 per month 100 GBStorage All Plans
Visit TresoritTresorit Review
$ 5.94 per month 200 GBStorage All Plans
Visit MEGAMEGA Review

What Makes the Best Zero-Knowledge Cloud Service

If you’re not quite sure what the difference between managed and private encryption is, we have a complete article on the basics of zero knowledge that will set you right.

We also have an online privacy guide focused on the best practices you can follow to keep you safe on the web, of which zero-knowledge encryption, along with finding a trusty VPN, plays a big part.

Finding the best zero-knowledge provider starts, of course, with making sure its a zero-knowledge provider. That leaves out some popular favorites, including Dropbox, Google Drive and OneDrive, unless you want to take your encryption DIY with a service like Boxcryptor.

After that, there are a number of things we considered. Since those who prefer zero-knowledge encryption tend to be focused on security, we looked for cloud services that did other things to compliment that calling, like two-factor authentication and passwords for shared file links.

We also considered elements of good cloud services in general, like value, sync capabilities and ease of use. So, basically all the same criteria that go into putting together our cloud storage reviews.

Now that the explanations are out of the way, let’s get to the important stuff: the winners.  

Best Zero Knowledge Cloud Service: has been one of our favorite cloud storage services for years now, and that’s an opinion largely propelled by the service’s unmatched approach to security.   First of all, you’re not charged extra for zero-knowledge encryption like your are with our second pick on this list, pCloud.

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On top of that, is one of the few cloud storage services to maintain zero-knowledge encryption even for shared files.

Besides that, also has an option for two-factor authentication and incorporates file sharing features to bolster security like passwords, expiry dates and download limits for file links. You can read more about’s approach to security in our full review.

It’s about as ironclad as cloud storage gets, with maybe only Tresorit coming close to matching it.

Other Reasons Why We Like

On top of being the most secure cloud storage solution we’ve ever used, also provides some of the best value. You can get a free 5GB account and add to that with an unlimited referral program, or you can just secure 2TB of space for about $8 a month. That’s easily one of the best deals in cloud storage.

pCloud and our second-place finisher, pCloud, have been playing tug-of-war with our heartstrings for a while now. You can read our latest thoughts on that subject in our vs pCloud head-to-head article.

We ranked pCloud second on this list mostly because zero-knowledge encryption costs extra with pCloud. You’ll need to purchase pCloud Crypto, which right now goes for $4.99 a month, though you’ll get a 20 percent discount paying a year in advance.

On top of that, files protected with pCloud Crypto can’t be shared, so it’s not quite as flexible as Files have to be placed in a separate Crypto folder, which is separate from the regular pCloud sync folder.

However, by not extending zero-knowledge encryption to all files, pCloud is able to do some things can’t, like stream music and preview images. It’s one of the best cloud storage for photos and media, which for some should make pCloud a better pick than

Other Reasons Why We Like pCloud

Aside from being almost as secure and more versatile than, pCloud is also just about as cheap. With a one-year subscription, you can get the same deal, 2TB for $8 a month, though remember you’ll have to pay extra for Crypto.

Overall, pCloud also has one of the nicer web GUIs we’ve seen, and is one of the few cloud storage services with a client for Linux (see our picks on best cloud storage for Linux).

SpiderOak ONE

Unlike our first two picks, our third selection isn’t a cloud storage service, its actually an online backup service. We have a full article on the differences between storage and backup, but basically it means that SpiderOak ONE is designed more for disaster recovery than complementing your hard-drive space.

However, SpiderOak is one of those services that blurs the line between storage and backup a bit. As you can read about in our SpiderOak ONE review, any files in your SpiderOak backup plan can also be synced and shared.

As an online backup service, SpiderOak ONE is very good, with support for backing up unlimited computers, continuous backup and unlimited file versioning. Zero-knowledge encryption comes included in the subscription price with SpiderOak, although that price is a bit more expensive than some of the alternatives in our best online backup guide.

Other Reasons Why We Like SpiderOak ONE

SpiderOak ONE takes a more structured approach to file sharing than most cloud services. It uses something called ShareRooms, which are kind of like password-protected shared folders, but much fancier. As with pCloud, be careful here: shared files lose their zero-knowledge protection.

While more expensive than online backup solutions like Backblaze (read our Backblaze review), SpiderOak is also more versatile thanks to its cloud features. However, that means it can be a bit trickier to use, so have a look at our how-to-use SpiderOak ONE guide if you’re stuck in a web of confusion.


There’s no question that Tresorit is one of the most secure cloud storage services available. Whether Tresorit is actually better for privacy than, you can read about in our vs Tresorit comparison. Zero-knowledge encryption is the key feature of Tresorit security.

Not only is it included by default, zero-knowledge encryption is extended to shared files. That fact, along with password protection, expiry dates and download limits for file links at least puts Tresorit alongside when it comes to secure file sharing.

Two-factor authentication is also an option, unlike with pCloud and SpiderOak ONE.

What hurts Tresorit on this list, and keeps it from vying for the top spot, is that it’s much more expensive than, pCloud and even SpiderOak. You can read about its unfortunately high cost of service in our complete Tresorit review.

Other Reasons Why We Like Tresorit 

Aside from being really secure, about the only thing we can say on Tresorit’s behalf is that at least has a Linux client, which puts it in rare company. While Tresorit is quite a bit more expensive than pCloud, we could easily argue that it’s the most privacy-focused cloud storage tool for Linux.  

Sadly, to figure that out for yourself, there’s not even a free Tresorit plan like you get with just about every other cloud provider. The best you can do is try the service out with a 14-day free trial before committing.  


MEGA’s inclusion in this list is more an indication of just how small the fraternity of zero-knowledge cloud services is rather than serious recommendation. MEGA’s got too many blemishes for that, although 50GB of free cloud storage might encourage a pretty big blindspot.


Zero-knowledge encryption is free, too, and extends to file sharing. The actual file-sharing process with MEGA, however, feels a bit clunkier than what you’ll get with most other cloud storage services. We have screenshots in our MEGA review.

MEGA also doesn’t offer any file versioning, which is rare. We’ve had some problems syncing large files, too, though smaller files copy just fine. Finally, if you ever want more than 50GB of storage, MEGA becomes expensive

Other Reasons Why We Like MEGA

As with Tresorit, there’s not much more to say. We could talk some more about why we don’t like MEGA. Or, just read this article about why Sync is so much better than MEGA.


Zero-knowledge security almost always means the service that includes it is probably going to be more secure than Dropbox. Whether or not they’re actually capable Dropbox alternatives depends on what more they do, though.

While we like because of its all-around great security and its value, those looking for a bit more flexibility might be better off with pCloud or SpiderOak ONE. If you’re looking for the most secure cloud storage for Linux, however, that crown might go to Tresorit over pCloud, and certainly over MEGA.

Use the comment section below to let us know your own thoughts on private, end-to-end encryption and the best cloud services to use it. Thanks for reading.

One thought on “Best Zero-Knowledge Cloud Services 2018”

  1. How do I protect against a complete crash on, say, Computer A; i.e., no computer no longer works. The no longer available Crashplan would allow me to restore the Computer A backup to a new computer. Is that possible with SpiderOne or Carbonite?

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