Cloud storage services have given us an easy, hardware-free way to back up and transfer files. Some of them even give you a little space for free. However, the key word is "little." Once you start uploading files and folders, that free storage fills up fast.

Before you go ahead and pay for extra room, try clearing out some of the junk in your cloud account. A full spring cleaning will make it easier for you to find the files you actually need, and save you from paying for an unnecessary upgrade. Here's how to keep a lid on your cloud storage in Google Drive, iCloud, OneDrive, and Dropbox .

Google Drive

When you're ready to clean up your cloud storage, start by examining how you've been filling up the existing space. In Google Drive, do this by visiting the web interface and looking for the storage-status link on the left side of the page, which should say something along the lines of "50GB of 100GB used." Hover the cursor over this link, and a window will pop up to show you how much room your files take up in Google Drive, Photos, and Gmail. You'll have to clean up each of these services separately.

Let's start with Google Drive. Click the Drive link to pull up a list of all your stored files, sorted by size from largest to smallest. Because the biggest ones appear at the top, it's easy to pinpoint the files hogging the most room. If you can live without some of these giants, then right-click on them and choose Remove .

In addition to cleaning out existing files, you should tackle one practice that causes them to pile up in the first place: automatic backups. Drive's Backup and Sync tool will upload and sync certain computer files to the cloud, and while you should definitely back up your files , you needn't store all of them online. To check which folders Drive is backing up automatically, head to your computer's settings: On a Windows machine, go to the notification area and click the Drive icon; on macOS, look for the Drive icon on the right side of the menu bar. Next, click the menu button (three vertical dots) and select Preferences . A screen will pop up to show you which folders are syncing to Google Drive. If you see folders that don't necessarily need cloud backups—particularly ones that take up a lot of room (the size of each folder appears on its right)—then untick the boxes next to them.

If your computer backs up photos and videos, those files will automatically land in Google Photos . To make sure they don't eat up all your space, Google can resize them to save storage room. Go back to the same Preferences menu, look under Photo and video upload size and select High quality (free unlimited storage) . Now Google will shrink too-large photos to 16 megapixels and videos to a resolution of 1080p. Although this may reduce image quality a bit, most photos and videos will still look great at those sizes, and they'll take up a lot less room in your account.

Even if your computer stops wasting storage space on bulky photos and videos, your smartphone could keep doing it. To change the resolution of phone-uploaded files, open the Google Photos app (for Android and iOS ) and tap the menu button (three horizontal lines) on the top left of the screen. From here, visit Settings > Back up & sync and toggle on the High quality (free unlimited storage) option.

Now that you've tidied up Google Drive and Photos, don't forget about Gmail. An email with a bulky attachment can use up space that you'd prefer to save for other files. Head to the Gmail website and run a few searches to clean out bulky emails. For example, to view messages larger than 5MB, type "larger:5m" into the search box and hit Enter (or change the size in question by replacing "5" with any other number). If you're worried about deleting a file that you may want again later, then add a time-period parameter to your search, such as "older_than:1y," which will bring up only emails that are at least a year old (again, you can adapt the time period by replacing "1" with a different number and/or swapping years "y" for months "m"). Once you've found the space-wasters, you can delete the irrelevant ones. Finally, if your Gmail is taking up way too much storage, you can go full scorched-earth and search for "has:attachment" to find—and potentially delete—any and all emails with attachments of any size.

At this point, you should have freed up plenty of space in Drive. To keep it that way, set a reminder to go through Google Drive, Photos, and Gmail periodically and manually delete unneeded files and emails. By setting aside 10 minutes once a month, you can easily stay on top of your cloud storage and prevent it from ballooning out of control.

iCloud

If you're an Apple devotee, then you probably back up your files, photos, apps, and email with an iCloud account . Considering that you only get a paltry 5GB for free, you may be stuck paying for extra storage. On the other hand, if your files only take up slightly more room than that, then you may be able to reduce the stored folders and bring them below that limit. As a first step, check on how much room you have left. On the iCloud web portal , for example, this information appears in the status bar at the bottom of the screen. The amount you have in storage will determine the amount you have to trim.

Next, check on the folders that are syncing to iCloud by default. From a macOS computer, click the Apple menu, then System Preferences > iCloud . Because the cloud-storage service backs up many Apple apps, you'll see categories for everything from Mail to Safari. But the biggest storage hogs are probably iCloud Drive and iCloud Photos. You don't have to stop syncing them, but if you dig into your settings for those services, you can back up fewer files from them.

To be more selective about your Drive folders, click Options next to that service, and untick any folders for which you don't need an iCloud backup. For example, if you keep a lot of junk in your Desktop and Documents folders, then untick the Desktop & Documents Folders option. Just make sure that you back up any important files from these folders elsewhere. Or, if you want to keep syncing those folders to Drive, then manually clear out room: Open Finder, click the Desktop or Documents folders, and drag outdated or unneeded files to the Trash. You can also erase files from iCloud Drive on the web by selecting a file and then clicking the Trash icon at the top of the page.

When you're done with Drive, go back a screen and click Options next to iCloud Photos. Although you can't clean up images individually, you can turn off automatic photo uploading via iCloud Photo Library . Even if you haven't downloaded iCloud's photo-storage app to a device, it might be backing up photos to your iCloud account through a related app called My Photo Stream. To prevent it from doing so, you can disable uploads from devices that haven't enabled iCloud Photo Library: Click Options next to Photos, then hit My Photo Stream and disable the setting. As a final measure, you can manually go through Photos and delete images or videos you don't really need to keep.

Another way to reduce photo clutter is to back up your images with Google Photos rather than iCloud Photo Library. Google offers backup tools for both iOS and macOS , and if you accept some resizing (a maximum of 16MP for images and 1080p for videos), you can store an unlimited number of photos and clips for free. That would leave more room on iCloud for document and app backups.

In addition to computer files, iCloud also keeps multiple backups of the information on your iOS device. You can delete the older versions to free up room, but it's best to leave your current device backup in place, in case you need it. To manage your iOS backups from a computer, return to System Preferences > iCloud , go down to the storage bar at the bottom of the screen, click Manage next to it, and open the Backups tab. You can also access the same screen on your iPhone or iPad by going to Settings > iCloud > Storage > Manage Storage and tapping on any backup to get rid of it. While you're managing iCloud settings on your iOS device, the same Manage Storage screen lets you turn off syncing for individual apps. Certain apps store data on their own servers, so you don't need to back them up with iCloud. Disable their syncing, and you'll free up a little more space.

Finally, if you sync Mail to your iCloud account, then emails with attachments might be taking up unnecessary room. To find and delete them, open the Mail app in macOS. Then go to Mailbox > New Smart Mailbox . Pick Contains attachments as the criteria and click OK , and you'll have a new folder that contains all emails with attachments. Go through it and trash the old emails that have large attachments you no longer need.

OneDrive

For Windows 10 users, Microsoft's online backup service OneDrive comes built into your machine. Even if you don't use a Windows 10 device, you can download versions of OneDrive for Android , iOS , and macOS . However, you only get 5GB for free, so you'll quickly reach a point when you need to clean out your OneDrive account.

Before you decide which files to delete, check out how much room they're taking up: Head to the OneDrive website , click the cog icon on the top right, and choose Options . Next, select What's taking up space? to see a list of all the files in your OneDrive account, sorted from biggest to smallest. You can erase files directly from this OneDrive web portal: Select them using the tick boxes to the top right of each thumbnail and then click Delete . They will disappear from both the OneDrive cloud account and from the OneDrive folder on your computer's hard drive.

Alternatively, you can delete the files in Windows or macOS. From Windows, OneDrive's natural habitat, open File Explorer , right-click on the OneDrive entry in the pane on the left, and choose Settings . In the Auto-save tab, you'll see which areas of your system—folders like Documents, Desktop, and Pictures—are automatically syncing with OneDrive cloud storage. If you can save copies of these files elsewhere, or they're not important enough to warrant backups, then go ahead and stop syncing them: Change the entry in the drop-down menu to This PC only . If you really want to cut out big files, then untick the box marked Automatically save photos and videos to OneDrive and back up these visual memories to Google Photos instead.

In addition to the Auto-save areas, you can sync specific items by dropping them into the OneDrive folder on your computer. When you want to delete one of these folders, you can untick it in the same File Explorer > OneDrive menu, but this won't remove the folder from your cloud storage locker—it will just delete it from the OneDrive folder on that specific computer. To also remove these items from the web version of your OneDrive account, then open the OneDrive folder in File Explorer (for Windows) or in Finder (for macOS). From here, either delete files or copy them to another location, and this will stop them from syncing to the cloud.

As a final space-saving measure, you can stop backing up your smartphone's files to OneDrive. Open the app on Android or iOS and go to Me > Settings > Camera upload . Turn this off to stop sending your smartphone photos and videos to OneDrive. If you'd still like to back them up, you can consign them to Google Photos for free.

Dropbox

Dropbox is one of the leading cloud storage services, and also has one of the lightest unpaid plans: You only get 2GB of free space before you have to start paying. That means to stay under the limit, you'll have to be extremely careful about what you store in Dropbox.

Because it doesn't offer automated clean-up tools, you'll have to manually delete files and folders. You can do this on the Dropbox website or from the synced Dropbox folder on your computer or phone. Deleting files in any of these locations will remove them from your cloud account and from the local disks where Dropbox is installed. If you accidentally erase a file, you can still restore it by going to the deleted files page of the Dropbox website.

Need some help prioritizing what to remove? On the Dropbox website, click one of the column headings, such as Modified or Members , and a little menu will pop up. Choose Size to sort the list by file size. This will show you which files or folders are taking up the most storage space, so you can delete the biggest ones first. You can arrange the list from largest to smallest or vice versa; just click the new Size heading to reverse the order. For folders, sizes won't appear automatically, but you can get an estimate by clicking the three dots to the side of any folder and choosing Calculate size . You can also erase files in bulk: Use the tick boxes to the left of each item to select a group of files and then click the Delete button on the right to remove them.

With its limited free storage, we don't recommend that you back up your smartphone photos and videos to Dropbox. If you still want to download the app (for Android and iOS ) onto your device, then turn off camera upload: Open the app, tap the menu button (three horizontal lines) on the top left, choose Settings , and hit Turn off camera uploads . That way you'll still be able to access Dropbox files from your phone, but you don't need to worry about every image taking up room in your Dropbox folder.

In Dropbox, other users can also eat up your storage space—by sharing their own files with you. If you no longer need access to certain items, you can remove them from your Dropbox. This won't affect the original files, which will remain in the Dropbox of the person who originally shared them. To see how much of your quota these shared files are taking up, head to the website and click your avatar on the top right, followed by Settings > Plan . If the number is high, you can go through your list deleting these files in the usual way. Unfortunately there's no easy way to display all shared files on their own—you'll have to go through your full list, looking for the share icon (two silhouetted portraits) that marks a shared file.

As with the other services we've mentioned, spending a few minutes every month or so deleting Dropbox files can really help you stay on top of your online space. But if you reach the point when you need a more drastic measure, try moving everything out of your Dropbox and putting it in another folder on your computer. Then you can add files back to Dropbox one by one, leaving out the unnecessary items.