Laws, projects and regulations around the world are turning privacy into a luxury. Chief among the countries that implement such laws is the U.S. Uncle Sam has the PRISM project, the USA Patriot Act and the CLOUD Act. The U.S. National Security Agency doesn’t mind making use of those laws, so having the best zero-knowledge cloud storage to protect your files is paramount.
That said, other countries aren’t far behind. Some EU countries sometimes act without regard to your privacy. The French have their own spying project and the UK passed the Investigatory Powers Act, which is even more frightening than its U.S. counterparts.
You can read more about privacy laws by country in our which countries have the best cloud privacy laws guide. Canada isn’t on that list because we did a separate article about the strong privacy laws in maple country.
With good privacy laws in place and adequate zero-knowledge protection, cloud storage services will help you clear space on your hard drive by moving your files to the cloud. Plus, your files will be safe from hard drive crashes and malfunctions. That’s important because it’s not certain data recovery software will be able to retrieve your files.
Best Zero-Knowledge Cloud Storage of 2020
- Sync.com★★★ Best Cloud Storage ★★★
- Sync Folder
- File Link Sharing
- Folder Sharing
- Visit Sync.comSync.com Review
- pCloud10 GB Free Storage
- Sync Folder
- File Link Sharing
- Folder Sharing
- Visit pCloudpCloud Review
- Sync Folder
- File Link Sharing
- Folder Sharing
- Visit TresoritTresorit Review
What Is Zero-Knowledge?
Zero-knowledge is an alternative name for private, end-to-end encryption. Private means that nobody but you can read your files. That’s because encryption is performed on your local device before the files are transferred to the cloud. Because you use a password that only you know for encryption, the files can’t be decrypted after transfer. That’s the “end-to-end” part.
That ensures your privacy because a cloud storage service that provides zero-knowledge can’t supply your unencrypted files to authorities. That said, if you forget your password, the cloud storage service won’t be able to reset it for you and you’ll lose access to your files. To avoid that, you should use one of the best password managers to store your password.
We’ve chosen our contenders from our best cloud storage services. If you’re looking for backup instead, read our list of the best online backup services. You can learn more about the difference between cloud storage and cloud backup here.
Before we get to our list of the best zero-knowledge cloud storage services, let’s define the criteria we used to make it.
What Makes the Best Zero-Knowledge Cloud Storage
Obviously, the cloud storage service has to offer zero-knowledge protection. We’ll make sure that it’s strong and doesn’t have loopholes that the company might use to invade your privacy.
Strong cloud security is also a must. It includes features such as the SSL/TLS protocol, which protect your files in transit, ransomware protection and more. Two-factor authentication, which protects your account, is important, too.
It’s best to have plans that provide more storage for cheap. The more plans the service offers the better because it’ll be easier to find one that fits your needs. If you’re looking for a great deal, check out our picks for the best deals in cloud storage.
An enjoyable and straightforward user experience is nice to have because it’ll make your interaction with the cloud storage service much more pleasant. An intuitive and easy-to-use interface will help with that. Plus, clients should work on the most popular operating systems and run on desktop, web and mobile.
How fast you can transfer your files will depend on your internet service provider, the cloud storage service and how close you are to its server. The closer you are to the service the better your connection speed will be. Transferring a lot of files might tax your computer, so it’s good if a service can limit system resource use. An option to throttle upload speed is good, too.
1. Best Zero-Knowledge Cloud Storage: Sync.com
Sync.com was founded in Toronto in 2011, and its dedication to strong user security and privacy helped it top this list and our cloud storage price comparison. It’s based in Canada, so you get the benefit of Canadian privacy laws.
It scrambles your files using AES 256-bit encryption and uses the TLS protocol to protect files in transit to its servers from man-in-the-middle attacks (Sync.com is our best encrypted cloud storage provider, too). The service is zero-knowledge-compliant. Plus, it provides two-factor authentication to help protect your password from hackers, but you should make a strong password regardless.
Sync.com’s data centers use RAID architecture to prevent server failures from leading to data loss and are SOC 1-certified. Thanks to those features, Sync.com is at the top of our most secure cloud storage list.
Before deciding to subscribe, you can use Sync Starter, a free plan that provides 5GB of storage. It’s not much, but it helps it make our best cloud storage with large service plans roundup. Still, it’s enough to see if Sync.com works for you. If you complete several steps, you can get 1GB of additional storage. You can also add 1GB per referral up to 20GB.
There are two personal plans: Personal Pro 500GB and Personal Pro 2TB. The former is $49 per year and the latter is $96 per year. There are no monthly plans, though. Still, those competitive prices make Sync.com’s plans some of the best in the market.
Business users can start with Business Solo, which supplies 2TB for $96 a year. Business Pro gets you 1TB per user for $60 a year. A minimum of two users is required and there’s a maximum of 50. If you need more storage space, you can subscribe to the Business Pro Advanced plan, which offers up to 10TB of storage per user for $180 a year.
Other Reasons We Like Sync.com
Sync.com’s desktop client is easy to use. You can access it via the taskbar icon. It works on Windows and macOS, but not Linux. If you want Linux support, read our best cloud storage for Linux comparison.
Sync.com’s transfer speeds are slower than average. The fact that its servers are in Ontario, Canada, and we were in Belgrade, Serbia, when we performed tests in our Sync.com review had something to do with that. You should expect to have faster speeds if you’re closer to its servers.
If transferring uses too much of your system resources, you can throttle the sync process. There’s an option to limit monthly uploads and downloads if you have a limited data plan, too.
Sync.com doesn’t use block-level sync. That’s normal, though, because block-level sync and zero-knowledge encryption don’t work well together.
Sync.com does a great job of ensuring users’ privacy and security, it has cheap subscription plans and it’s easy to use, all of which helps it top this list.
- Strong security
- Great value
- Good ease of use
- No monthly plans
pCloud is a Switzerland-based company but it keeps your data on Uncle Sam’s ground. Thankfully, it provides zero-knowledge encryption to balance that. What’s not so good about it, though, is that you need to pay extra to get it.
pCloud calls its private encryption “pCloud Crypto,” and you need to pay $3.99 per month to use it. We suggest you get it considering the U.S.’s laws and regulations. Plus, we’ve heard from readers that pCloud will go through your files to make sure nothing violates its conditions of use if you don’t use Crypto (read more in our what is pCloud Crypto? piece).
As a testament to its security, pCloud hosted a pCloud Crypto hacking challenge, but nobody was able to complete it.
Besides private encryption, pCloud uses the TLS/SSL protocol to protect files during transfer and AES 256-bit encryption to protect them at rest. When files reach one of its data centers, five copies are created and distributed to at least three servers. The data centers are secured and monitored 24/7.
pCloud uses two-factor authentication to protect your account if someone steals your credentials.
Before subscribing, you can use the free plan, which gives you a generous 10GB of storage. You can complete several steps after registering to get an additional 4GB of free storage. Plus, every friend you refer gets you 1GB of additional space up to 20GB. Thanks to that, it’s at the top of our best cloud companies with large free plans list.
Like Sync.com, pCloud only has two personal plans, but they’re competitive. The Premium 500GB plan is $4.99 per month and the Premium Plus 2TB plan is $9.99 per month. If you pay for a year in advance, the prices come down to $47.88 and $95.88 per year, respectively.
If you think pCloud is great and you want to use it for a long time, you should buy a pCloud lifetime license because it’ll save you a lot of money in the long run.
Other Reasons We Like pCloud
Using the desktop client is enjoyable and easy. You can access it with the system tray icon or the pCloud drive in your system files manager. The interface is somewhat drab, but it’s clear and intuitive. It’s available for Windows, macOS and Linux.
If you’re on a different computer and need to access your files, you can use the web interface. It’s fast, has more features and offers a fluid experience. It’s not good for transferring large files, though, so you should use the desktop client for that (read our how to use pCloud Transfer guide).
The mobile app is also easy to use. You can use it to automatically upload photos and to play audio and video files. It’s available for Android and iOS.
pCloud keeps its servers in the U.S., but it performed much better in our tests than Sync.com. The transfer speeds matched what we expected given our connection speed. You can limit speeds manually if pCloud takes too much of your bandwidth. Read our pCloud review to learn the details about our speed tests.
pCloud charges extra for zero-knowledge encryption, which is the main reason we placed it behind Sync.com.
- Excellent value
- Good ease of use
- Private encryption is a paid add-on
- U.S. privacy laws
Tresorit is one of the most secure cloud storage solutions thanks to its zero-knowledge encryption and other security features. It requires you to pay more to enjoy them, though.
The service uses zero-knowledge encryption to protect your privacy, the TLS protocol to prevent attacks that target files during transfer and AES 256-bit encryption to protect files at rest. Plus, two-factor authentication is available to protect your account in case someone cracks your password.
Tresorit holds its servers in Microsoft Azure data centers in Ireland and the Netherlands, read our Microsoft Azure review to learn more.
Tresorit replicates your files on multiple servers in a data center to reduce the risk of data loss and increase the availability of your files.
There’s no free plan, but you can use a free trial to test it. The cheapest plan is Premium at $10.42 per month for only 200GB of storage space. Solo is the other personal plan, and it provides 2TB of space for $24 per month.
Tresorit also has business plans. Small Business is $20 per user per month and gives you 1TB of storage for each user. Business is on a 50 percent discount at the time of this writing, which makes it $12 per user per month. Enterprise is $24 per user per month and supports more than 100 users.
Other Reasons We Like Tresorit
Tresorit is among our best cloud storage services, but its user experience is more complex than average. That’s because you need to create individual tresors to sync files. The desktop client works on Windows, macOS and Linux. Sync is complex, but the desktop client is clear and easy to use. It’s also one of the most attractive on the market.
You can use the Tresorit web app to access your cloud storage. It has a minimal design, so it’s easy to navigate.
Tresorit’s smartphone app works on Android and iOS. You can use it to access your storage, work offline and upload photos and videos from your phone. Plus, you can secure it with a passcode lock.
Tresorit’s upload speeds are average, but the download speeds are slower than they should be. If you find that Tresorit interferes with your work or you’re on a limited data plan, you can limit the network bandwidth. You can read more about Tresorit in our Tresorit review.
- Dedicated to security
- Good platform support
- Complex sync
MEGA was launched in 2013 by Kim Dotcom, and it’s one of the most controversial cloud storage companies. It has strong security that features zero-knowledge encryption, though (our pCloud vs MEGA comparison shows MEGA has better privacy).
The level of encryption at rest is AES 128-bit which isn’t as strong as AES 256-bit, but nobody has been able to crack it as far as anyone knows. It also uses the TLS protocol to protect data during transfer. It offers two-factor authentication, too.
MEGA has four plans, but none can match the values of the top two services on this list. PRO LITE is $5.69 per month and gives you just 200GB of storage space. For 2TB of storage space, you have to subscribe to the PRO II plan, which is $11.38 per month. If you pay for a year in advance you get two months for free.
What makes MEGA more enticing is its free plan which initially offers 50GB of free space, but that goes down to 15GB because 35GB expire after a while.
Other Reasons We Like MEGA
MEGA’s desktop client is attractive, clear and won’t leave you scratching your head. It works on Windows, macOS and Linux.
The web interface is user-friendly and straightforward, too. It has one of the best drag-and-drop features because you can drop your files practically anywhere.
You won’t have issues with mobile apps, either. It’s available for Android and iOS. The main part of the screen lets you access your files, while the bottom menu lets you access chat and the camera, upload and view shared folders and your offline files. You can also set the app to upload your photos and videos automatically.
MEGA keeps its servers in Europe, Canada and New Zealand. That didn’t help us achieve the speeds we expected, though. MEGA was slower than average. Plus, there are a lot of comments on our MEGA review complaining about slow speeds.
- Large free plan
- Great user experience
- Speeds can vary
- Prices could be better
Woelkli is based on Nextcloud, which helps you build and maintain your own cloud storage. If that interests you, read our best DIY cloud storage tools article. Woelkli keeps your files in Switzerland, so you can enjoy some of the best privacy laws in the world.
You won’t have to rely on those laws, though, because Woelkli has zero-knowledge encryption. Woelkli can’t recover your password by default, but you can turn zero-knowledge off if you think you might forget your password.
Woelkli uses the TLS protocol and AES 256-bit encryption, which scrambles your files at rest. To protect your account, Woelkli uses two-factor authentication, too. Plus, Pro users can scan their files using ClamAV to protect their devices from trojans, viruses and more.
Woelkli’s free plan only provides 1GB of storage space, but that’s enough to get a feel for how the service works.
Woekli’s paid plans are among the most expensive on the market. For 10GB of storage space, you have to pay $7.54 per month. The next plan, Level C2, doubles the price and increases your storage five times to 50GB. Its other plans don’t do much better.
Its business plans are also expensive and don’t offer sufficient storage for what most businesses need. The first plan starts at 10GB for $402.45 per year, or $33.53 per month, which might be enough for a single user. Level C6 provides 100GB, but it’s $8 per month more. The largest plan gets you 500GB and costs $83 per month. Prices don’t include a 7.7 percent VAT.
Other Reasons We Like Woelkli
Using the desktop client isn’t straightforward because Woelkli is based on Nextcloud. That requires you to install Nextcloud and connect to Woelkli.
The web client is a different matter, though. It’s fast, attractive, intuitive and easy to use. The smartphone app is also easy to use because it’s similar to apps from other cloud storage services. It lets you upload files, take a photo and upload it and upload content from other apps.
Your transfer speeds will depend on how close you are to Switzerland. Our tests showed that Woelkli has speeds that can compare to other services. By default, Woelkli doesn’t restrict bandwidth, but you can do so if you wish.
We placed Woelkli last because it’s expensive and not straightforward to use. If you want to learn more about it, though, read our Woelkli review.
- Swiss privacy laws
- Bland desktop client
Honorable Mentions: Best Zero-Knowledge Backup Providers
If you’d rather backup your files and need a service to help you do that, you should look no further than IDrive, Acronis True Image and BigMIND Home. They’re at the top of our best online backup comparison list.
IDrive is our top pick, though, thanks to its competitive pricing, strong security and the ability to backup unlimited external devices. Its features include social media backup, network-attached storage backup and advanced backup scheduling and restore options. Plus, like cloud storage services, it can sync and share files. Learn more about IDrive in our IDrive review.
Acronis True Image has strong security features including active protection against ransomware. It also provides many tools in its desktop client that help you manage your backup. You can also install third-party tools, backup Facebook and Instagram and sync files, too. Read more about it in our Acronis True Image review.
BigMIND Home lets you preview your multimedia files, use its AI features to manage photos, enjoy its free plan and backup from other cloud services, including Facebook, Instagram, Google Drive, Microsoft OneDrive and Dropbox. BigMIND Home also lets you share and sync files. You can read more about its many in our BigMIND Home review.
When it comes to protecting your privacy, zero-knowledge encryption is your strongest ally. All the services on our list have it, but they differ in other categories. That said, all have strong security so you have to rely on other factors to make your decision, most notably the price.
Though the first two services, Sync.com and pCloud, are competitive, others fall behind. That goes for speed, too, because Sync.com and MEGA are slower than average. Still, Sync.com is our top pick thanks to its strong security features, good ease of use, cheap plans and Canadian privacy laws.
Woelkli relies on strong Swiss privacy laws, but that doesn’t help it beat the other services.
What do you think about our picks? Did we miss a service? Which cloud service that protects your privacy do you use? Check out our best VPN services for a better privacy overview and leave your response in the comments below. Thank you for reading.