Review: 4 online backup services keep your data safe

We test cloud backup software from Mozy, Carbonite, Acronis and IDrive. Find out which offers the best security, speed, features, interface and price.
  • Brian Nadel (Computerworld (US))
  • 06 September, 2017 06:46

In the 15 years that I’ve been running a small company, I have survived several malware attacks. The only thing that kept me in business was a reliable backup of my data.

When it comes to my data (if not my pants), I’m a belt and suspenders kind of person: In addition to periodically copying my two key work folders onto an external hard drive, my system automatically backs up my computer’s contents to an encrypted cloud-based backup service at 1 o’clock every morning.

If I’m attacked or my main computer goes south, I won’t lose my company’s 40.9GB of data, even if some catastrophe destroys both the computer and the external hard drive. More than once, I have used the backups to save my digital bacon by retrieving a deleted file, and the online backup has the added convenience of letting me use just about any connected device to access a document and show it to a client during a remote meeting.

I’m not alone in recognizing the benefits of online backup. Phil Goodwin, research director of IDC’s Storage Systems and Software group, says, “Many small business owners use consumer backup services to protect their company’s data. It’s good protection at a good price, with no hardware required, and has the ability to share saved files wherever you go.”

For this evaluation, I looked at products from four top vendors in the online backup world, according to Goodwin: Mozy, Carbonite, Acronis and IDrive. I also tested a fifth product, Code42’s CrashPlan for Home, but after the review was done and before publication, Code42 announced that it is phasing out CrashPlan for Home and will stop selling that product as of Oct. 23. We removed that review from the story, but we do provide some details about CrashPlan’s surviving small-business product below.

Of the four remaining products, Carbonite offers unlimited storage but restricts the types of files you can back up. Acronis, IDrive and Mozy charge on a per-gigabyte basis but are less restrictive about what you can save.

One thing all of the vendors share is an emphasis on security, with data encrypted both in transit and during storage on their servers. Acronis goes a step further by using blockchain technology to make sure that the backup you need to rebuild your system hasn’t been tampered with.

To evaluate these online backup services, I timed a series of backups and file restorations using a Windows 10 laptop. I then timed how long it took to retrieve a file stored in the cloud to an Android tablet. (The Android results are given throughout the story, but Mac results were similar.) See “How I tested” for details.

The results were eye-opening. Read on to find out why.

Acronis True Image 2018 Premium

Acronis True Image 2018 offers fast backups and extras such as top security and the innovative integration of the blockchain technology used by the bitcoin cryptocurrency.

Acronis offers a 30-day free trial. There are two subscription online backup services, Advanced and Premium, either of which you can purchase for one, three or five computers. (There’s also a Standard option that doesn’t include online backup and has no annual fees.) The Advanced edition includes backup and recovery, disk cloning, mobile device backup, social media backup and cloud storage of up to 250GB for $50 per year.

The Premium edition, which I reviewed, adds electronic signatures for documents and Blockchain verification that the archives haven’t been altered. It comes with 1TB of online storage and costs $100 per year.

At 498MB, the Acronis app is the largest of the group to install by a wide margin, but it is also the deepest, with a slew of utilities. It took three minutes to download and install it.

The Acronis interface is clean and uncluttered. The column on the left provides quick navigation to functions such as backup, archive and sync, as well as to a dashboard that provides access to backups of your computer, your phone and tablet, and your Facebook material.

The backup screen shows the file flow from local system to cloud, including a progress bar. It has convenient “Back up now” and “Recover files” buttons. True Image can run a full backup, or you can choose to exclude some file types from the backup process.

online backup software - Acronis Brian Nadel / IDG

The Acronis dashboard showing a backup in progress. The clean portal design includes succinct navigation on the left. (Click on any image in this story to enlarge it.)

Backups can be scheduled at daily, weekly or monthly intervals, or Acronis can continuously back up files as they’re saved. It can also be set up to automatically perform a full backup after a restart or shutdown. You can also set up True Image to do backups only when your system is idle, choosing between optimal and maximum speeds.

Overall, I found that the True Image 2018 interface provided the best balance between getting a good overview and getting things done. It’s easy to find what you need, and at any time you can dig deeply to change what is being backed up and whether it’s being saved locally or online. On the downside, you can’t just drag and drop files or folders that you want to back up, but instead must select them from a Windows Explorer-like interface.

Extra security

One thing that distinguishes Acronis from its peers is its use of blockchain technology as part of its Notary feature, which helps determine whether someone has altered your online archives. Notary issues a certificate attesting to a file’s authenticity from Ethereum Foundation, a major blockchain developer.

Besides Notary, True Image offers what it calls Active Protection, which senses when files are being systematically altered. It calls this “ransomware protection,” and here is the logic behind that: Security experts widely tout consistent and frequent backups as the best way to avoid paying ransoms to unlock maliciously encrypted files, but cybercriminals can short-circuit that protection by messing with your archived files as well as those on local systems.

When True Image detects behavior that doesn’t match what it has learned about how you interact with your archived files, it stops the activity and restores your backup files. It can be set to automatically restore the original file.

Besides the online backup, you can have True Image archive files locally on an external drive, but Acronis will neither send you a drive with your files (as Carbonite does) nor allow an initial hard drive upload (as IDrive does).

The True Image app is available for Windows, macOS, iOS and Android, but you don’t have to use the app to retrieve files; most web browsers, including Chrome, Internet Explorer, Edge and Firefox will work.

online backup software Acronis Android app Brian Nadel / IDG

Searching for a document to restore (left) and starting a backup (right) using the Acronis Android app.

On top of backup, Acronis provides a wide variety of utilities, such as system and drive cleanup apps. The software provides the means to easily clone a hard drive or set up a protected partition on an external hard drive for local backups.

Test results

True Image 2018 is for those in a hurry. At 2 hours, 49 minutes and 11 seconds, it did the fastest initial backup — one-fifth the time of the Mozy backup. Its 4.13MBps throughput was the best of the bunch.

The service took 41.2 seconds to perform an incremental update, which was slightly slower than Carbonite’s 30.8 seconds, but it was essentially tied for fastest at restoring a 130KB image file, taking 8.1 seconds to Mozy’s 8.2 seconds. And the service took only 5.1 seconds to transfer that same 130KB image file from the cloud storage to my Android tablet, the fastest of the lot.

Bottom line

At $100 for a year’s worth of 1TB of storage space, Acronis True Image 2018 Premium is a great value. Besides storing all your files, it protects against ransomware intrusion and uses blockchain technology to prove that the backups haven’t been tampered with. For Acronis, security is a true differentiator. No other backup service provides more peace of mind for the money.

Carbonite Personal Prime

Unlimited cloud storage! Those are seductive words for anyone shopping for an online backup service, and it’s the promise of Carbonite Personal. One-year subscriptions are $150 for the Prime service, $75 for the Plus service and $60 for Basic, and Carbonite offers a 15-day free trial. Subscriptions cover one machine, whether it’s macOS or Windows. (If you want to back up a machine running Windows Server, you’ll need one of the pricier Carbonite Office plans, which cover an unlimited number of computers.)

File retrieval isn’t restricted to one machine, though. In fact, Carbonite has mobile apps for Android and iOS devices, and you can also use a web browser to grab any saved file.

What’s more, Carbonite offers a backup of your backup. If for some reason you can’t rebuild your data from the online repository, Carbonite’s Courier Recovery Service will ship you a USB hard drive containing every backed-up file. For Carbonite Prime customers, this service costs $10 per use, including shipping, but the company charges $130 if you don’t return the drive. (The charge is $100 for Basic and Plus customers, so one use would double a Plus customer’s annual backup costs — and more than triple them if you don’t return that drive.) For Prime customers, it’s a bargain compared to Mozy’s similar feature.

online backup software - Carbonite recovery screen Brian Nadel / IDG

Carbonite’s desktop file recovery interface lets you browse or search to find the files you want to recover.

The 15.9MB program takes about three minutes to get and install. Once the software is installed, you can take a tour of its features, and you will be asked whether you want to store the 256-bit AES encryption key yourself or have Carbonite manage it for you. Keep this in mind, though: If you choose to hold your encryption key, you can’t use the mobile apps to view files.

Carbonite’s unlimited storage might lose some of its luster in your eyes when you see the types of files and folders it won’t back up, at least not automatically. Several file types (those larger than 4GB, for example, or those outside of Windows C:\Users locations, or Mac Mail and Calendar files) won’t be backed up automatically but can be included if you manually select each one. Besides that, Carbonite has long lists of file types specific to Windows and macOS that it won’t back up at all. In addition, the company holds deleted files for only 30 days and it’s a single-use license.

My favorite feature of Carbonite is that you can use Windows Explorer (a.k.a. File Explorer) to see which files have been backed up. Carbonite adds colored dots next to an item to show whether it has been backed up or is awaiting action; a half-filled dot next to a folder means that only some of the files it contains have been designated for backup.

online backup software - Carbonite Windows Explorer Brian Nadel / IDG

In Windows Explorer, small colored dots show which files and folders Carbonite has backed up.

Carbonite’s half-size screen can’t be resized or moved. You can use the app to schedule backups or choose to continuously back up files, set up a nightly archive and pause the backup process. Its array of customization options pales in comparison to those offered by Acronis.

Test results

During backups and recoveries, Carbonite stopped dead in the digital water a few times. Its initial backup of 37.8GB took 5 hours, 13 minutes and 6 seconds, more than two hours longer than Acronis’s initial archiving, with throughput of 2.01MBps — half that of Acronis.

Its 30.8-second incremental update of 86MB was the fastest of the five. The service replaced a deleted file in 13.3 seconds for middle-of-the-pack performance, and it came in last when grabbing an online file from my Android tablet, at 18.6 seconds.

Bottom line

At $150 per year for the Prime service, Carbonite is expensive compared to Acronis and IDrive — unless your single computer holds more than 1TB of data to be backed up. The local mirroring and hard drive delivery service are nice contingencies, but if you’re comfortable with strictly online backup (or are willing to do your own backing up to an external hard drive), the Basic and Plus plans could be good, cheaper options. Carbonite is a good option when you have one computer with a lot of data you can’t afford to lose.

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IDrive Personal

IDrive Personal will archive files from as many computers as you have. As with Acronis and Moby, you’ll need to pay for the online storage space, but IDrive is the least expensive backup service of the four services reviewed here, and if you have a lot of data, it can be a bargain.

There’s a free Basic service that offers 5GB of storage space for those with limited backup needs. In my tests, I set up the lower tier for the IDrive Personal 1TB plan, which at the time cost $70; since then, however, this plan has doubled in size to 2TB while falling in price to $52 for a year. That is just over half what Acronis charges, for twice as much storage. There’s also a 5TB tier of IDrive Personal that’s $75 per year.

If your data provider meters your online use, IDrive can ease that first big backup with IDrive Express. The company sends you a USB hard drive onto which you transfer up to 3TB of files, then ship back to IDrive. Within a day of when IDrive receives the drive, the files are typically online and ready. It’s free (including shipping) to use once a year.

The service’s 20.2MB Windows app can be downloaded and installed in three minutes. IDrive’s busy interface has links on the left for Backup, Restore, Scheduler, Sync and Settings. There’s also a page that lets you back up Exchange, SharePoint and other servers.

online backup software - IDrive backup screen Brian Nadel / IDG

IDrive’s interface is a little busy, with redundant navigational cues that some may find annoying and others may find handy to get to various features.

The service can be set to back up every file. They’re all encrypted using the 256-bit AES cypher, but the service lacks Acronis’ blockchain technology to verify a backup file’s authenticity. You can keep your own encryption key.

Dig deeply and you can set up continuous backups as well as image the entire machine onto an external drive. The app lets you throttle your upload speeds as well as schedule your daily backups.

IDrive has a powerful scheduling function that lets you set up backups for the middle of the night. It not only lets you establish a cutoff time for long backups, but (optionally) sends you an email notification when it’s done.

online backup software - IDrive scheduling backups Brian Nadel / IDG

Setting up a backup schedule in IDrive is easy.

In addition to online storage of backups, IDrive lets you mirror the system’s image on an external hard drive as well as back up Facebook items. You can add folders to the backup and exclude file types.

There are apps for Windows PCs, Macs and Linux computers, as well as mobile apps for iOS and Android devices. Those on the go can view any file via a web browser.

Test results

As the files flow from the system to the server, IDrive shows a progress bar and an estimate of how much time remains. IDrive’s initial 41.8GB backup was accomplished in 7 hours, 46 minutes and 41 seconds, for a disappointing throughput of 1.49MBps — less than one-half as fast as Acronis, but faster than Mozy.

Its 42.4-second incremental update was right in the middle of the services tested. The service restored an image file to my Windows PC in 11.3 seconds and retrieved the file from the cloud to my Android tablet in 12.7 seconds, in the middle of the pack for both.

Bottom line

Got a lot of computers to protect? IDrive can back up all of them fairly efficiently and keep all the data online. And at 2TB of cloud storage for $52 or 5TB for $75, it offers the best bang for the buck in this roundup.


Mozy’s MozyHome service uses parent company Dell’s EMC data infrastructure to securely hold your documents, images, documents, music, videos and other key files. It ignores things such as .aci, pagefile.sys and even some Mozy program files.

There’s a free service that provides 2GB of storage space, and you will be awarded with 256MB of extra storage for every acquaintance you refer to Mozy. I used the $120 annual plan that includes 125GB of space and can back up three computers. By contrast, IDrive offers 16 times as much space for about $70 less.

Mozy matches Carbonite by promising to send you all your files on a hard drive if for some reason you can’t retrieve them from the cloud, but Mozy charges $30 for processing, $40 for shipping and 50 cents per gigabyte. For instance, if you have 100GB saved online, it would cost $120, making it quite expensive compared to Carbonite Prime’s similar service. The Home service doesn’t let you jump-start the backup process by shipping your files on a drive to Mozy, but Mozy’s Pro service does.

You can back up data locally on an external hard drive. In addition to software for Windows PCs, Macs and iOS and Android devices, you can also get any saved file with a web browser.

The 12.5MB MozyHome Windows app took 1 minute and 15 seconds to load and get started, easily the fastest of the group. When you set up the program, the company offers the choice between using a 448-bit Blowfish cypher, with Mozy managing the key, or 256-bit AES encryption, with you choosing the key. It lacks Acronis’ ability, though, to add blockchain technology to prove that your archives haven’t been changed.

online backup software - MozyHome backup screen Brian Nadel / IDG

Mozy’s backup interface has two windows, which can be a bit confusing.

The interface is a bit tricky to figure out, with two windows to deal with. I often found myself looking at the wrong one. The Settings page can run full size and shows Backup, File System, Options, History and Restore; it has a Welcome screen that explains the app.

Mozy also has a smaller Status screen that shows what needs to be backed up and what has been sent. It lacks a progress bar or estimate of time remaining, but the program’s task tray icon slowly turns green from left-to-right to show progress.

There’s a lot to customize with the Settings screen, including scheduling backups. You can throttle the bandwidth used and adjust between having a faster computer or quicker downloads.

online backup software - MozyHome Brian Nadel / IDG

You can decide how much of your internet connection Mozy can use with the Throttling Parameters setting.

Test results

Mozy was the slowest of all the services tested, with an initial backup of 31.6GB taking an excruciating 13 hours, 44 minutes and 25 seconds, for an average 606KBps transfer rate. It’s best to set it up for an overnight upload.

The service’s 64.2-second incremental backup was also the slowest of the five and more than double that of Carbonite’s service. Its file recovery efforts were more satisfying, retrieving the test image file in 8.2 seconds on the Windows PC. While the service was able to show a thumbnail of the target online file in 2 seconds on my Android tablet, it took a total of 13.9 seconds to download the entire 130KB file.

Bottom line

In addition to using an awkward two-fisted interface, MozyHome was the slowest of the four at backing up and restoring files — and at $120 per year for a meager 125GB of online storage, it’s the worst deal of the roundup.

Pricing and test results compared


Success in backing up your vital data comes down to the three S’s: speed, security and software. All four of the backup services I looked at fulfill the minimum here, although all but one fall short in one area or another.

For instance, Mozy lets you pick your encryption method, but its double-barreled approach to software is hard to understand, and its annual cost per storage offers poor value. Plus, if time is of the essence, steer clear of Mozy, because it’s the slowest of the four by a wide margin.

Even though its backup was six hours shorter, IDrive still took too long to do its initial backup. At least the company recognizes that shortcoming and lets you send it a hard drive of your files for a less frustrating start. On the plus side, its interface allows lots of customization, and IDrive offers 2TB of storage space for $52 — the best deal here.

Carbonite offers unlimited space to put your files, but limits what file types you can store. While the service offers to send you a hard drive with all your files to ease a recovery, it gets rid of your files after an all-too-short 30 days.

online backup software Acronis Notary certification Brian Nadel / IDG

Acronis is alone in this group in offering file verification using blockchain technology.

Acronis’s True Image 2018 had a clean sweep in terms of speed, with the fastest backups, and software, with an easy-to-learn interface that provides a good overview and access to the details without being overwhelming.

It also stands alone in terms of security, with top-rank encryption, a way to protect against ransomware, and blockchain technology to show that a backup hasn’t been altered. In other words, you know that the backup is not only yours, but it hasn’t been compromised. It’s a big deal, and as soon as the subscription with my current online backup service expires, I plan to switch to Acronis True Image.

How I tested

To measure how these online backup services rate and compare, I downloaded each app onto a Wi-Fi-connected HP EliteBook Folio G1 laptop running Windows 10 Pro and set up an account for each service. After nosing around to get the feel of the program, I started the heavy work of backing up its array of files, which includes a folder on the desktop that contains 40GB of work data composed of 40,700 files, ranging from documents and images to accounting records, presentations and videos.

Before running the backup, I tested my online connection using’s online benchmark. I then timed how long it took to perform the initial backup using the service’s default settings. I finished by once again testing the available bandwidth.

Next up, I added 11 files totaling 86MB as the typical product of a workday’s toil and timed how long it took to back up this incremental data. The files included videos, PDFs, spreadsheets, images and presentations. I then simulated a file loss by deleting a 130KB image file and timed how long it took the program to restore it.

Finally, I grabbed the same image file from the online archive and timed how long it took to display it on an Android-based Asus ZenPad 8 and an Apple MacBook Air notebook. The Mac performance was in line with the Android results, so for the sake of simplicity I reported only the Android results.

After the digital dust had settled, I wiped the backup software from the system and started on the next one.