How to Resize Pictures (for Macs) In this Article: Resizing an Image in Preview Cropping an Image in Preview Community Q&A Resizing an image on your Mac is simple with Preview, a free image utility that comes pre-installed on OS X. Preview helps you crop images easily and adjust their dimensions without having to install additional software. IFunia Photo-Resizer for Mac is a simple photo resizing tool that allows users to resize, rename the photos in a quick and easy batch mode. With it, users can easily adjust the size of photo by percentage, by height, and by aspect, or can even enter the custom size that wanted.
A lot of us will unanimously vouch that iPhoto 11 is the best way for Mac users to manage, edit, and share photos, but some Mac users may not take enough photos to warrant purchasing or bothering with the program. In addition, you may simply need to quickly resize images without bothering to open iPhoto, which sometimes can mean opening a huge library of thousands of images.
For more streamlined purposes, Apple’s default OS X applications, Preview and Mail, and a free lite version of a third party application called ResizeIt may suffice. If you, on the other hand, need to do batch resizing of images, check out my article5 Quick & Easy Mac Automator Hacks for Digital Photos5 Quick & Easy Mac Automator Hacks for Digital PhotosRead More on using Automator for this purpose.
Resizing In Preview
By default, when you double-click on an image on your Mac, Preview is the application that opens it up. What you may not know is that it’s also a good application for resizing images. To do so, open an image into Preview, and click Tools > Adjust Size in the menu bar.
The drop-down window will provide you information about the dimension and resolution size of the image. For images you’re going to post for viewing on a website, the resolution size 72-150 pixels is adequate. For printing purposes, 240 to 300 pixels should be used. You should manually type in the dimension for resizing your image.
Or you can use one of the presets provided in Preview. It used to be that 640 x 480 pixels was the standard size for posting images on the web, but with many people viewing the web on widescreen monitors and small mobile phones, you might need to consider other sizes, such as 800 x 600 or the smaller 320 x 240. Unfortunately, Preview doesn’t allow you to save custom sizes as a preset. If you have a custom size you need to regularly use, create an Automator workflow5 Quick & Easy Mac Automator Hacks for Digital Photos5 Quick & Easy Mac Automator Hacks for Digital PhotosRead More or use ResizeIt described below.
Caution: when you resize images in Preview it will not give you the option to save the original of your image. So you need to either make a duplicate copy of the photo before resizing, or select Save As to make sure you’re saving the resized image as a separate file.
Resizing In Mail
If you want a super fast way to resize an image(s), simply drop it into your Apple Mail application and mail it. Done. Mail even provides you with options for resizing.
At the bottom of the composition box, Mail will tell you the dimensions of the resized photo before you mail it. You can change it to Small, Large, or Actual Size, provided the recipient of your email has a fast enough Internet speed to download a large size image file.
The great thing about using Mail to resize an image is that it doesn’t resize your original. It makes a copy and then resizes it. However, if you try to drag the image out of your drafted email, it will not be the resized version.
Resizing In ResizeIt
If you don’t want to haul out iPhoto or Photoshop to resize an image, and if you need to do some quick batch resizing of images, a small free application, ResizeIt available in the Apple Mac Store, may do the trick. Now I must say, ResizeIt could use some work, although it does what it says it will do.
The best way to use ResizeIt is to select, then drag and drop one or more photos onto the ResizeIt icon in your Dock. From there you will be presented with a dialog box in which you configure the settings you need. Be sure to leave the Overwrite Files box unchecked if you don’t want to resize your original image(s). If you leave the “Choose the folder to save images” unchecked, ResizeIt will resize, save, and put your images into a folder for you.
You can also save various sizes as presets. The application worked OK for me. I do think however that the pixel boxes should start with “W” and then “H”, for that’s typically how dimensions are set in image applications. The first number is usually the width and the second is height. But ResizeIt is a free application, so not much to complain about. It’s a useful program for quick batch resizing.
Finally, if you click on Script > Generate Droplet, ResizeIt will produce an AppleScript script that you can save as a droplet application. It‘s sort of like creating an Automator application for resizing images. So for example, if you regularly need to resize photos to a particular size, like 800 x 600, then you simply create the preset in ResizeIt, and then have the application create a droplet for that size. The code will open up in AppleScript and you can save it as an application that you can keep in your Dock. From there, you just drop your images onto the droplet and, viola, they get automatically resized. That‘s the way computers should work.
The key to resizing images is to have as many options to do so. No one wants to receive or view an oversized image. Let us know if you have any other strategies for resizing images. For Windows users, check out Simon‘s article on resizing photosThe Top 3 Apps to Batch Rename, Convert & Resize Photos (Windows only)The Top 3 Apps to Batch Rename, Convert & Resize Photos (Windows only)Read More.
In an article that’s soon to follow, we will give iPhoto it’s due when it comes to resizing photos. Stay tuned.
Explore more about: Image Editor, Photography.
Thank you for writing this article. I am trying to resize a pdf in Preview but when I go into Tools the 'Adjust Size' option is greyed out. Any ideas? Many thanks again, Kate
I have double clicked on my image and I can't find tools. All I can find is edit tools. I'm on a new Mac pro. It's a steep learning curve for an older PC user!
Toni SAME here my MAC is SO different from windows Maybe this thing is not for Mac users .:( I cannot even find the TOOLS button to try to re size
rite I want to put my photos in year files but it still seems to be in 2 different places i would just like file 2011, 2012, 2013.. and find the photos there not in different albums . it it possible? please surest anything x
Bakari Chavanu, I just wanted to say, Bless you for writing this article! I was having the hardest time trying to figure out which app. to use to resize or even locate some tool in the software that would assist in reducing the size of my photos and then came across your article. Very helpful.
Oh wow thank you so much for writing this article! I am building my website, and have used ImageWell in the past but it's not functioning and no support. Sooo I thought my only way to resize on my mac was in iphoto. So much easier in preview. I never looked at what was under those headings! Thanks again. You have saved me a lot of time.
Thanks for the tips. If you want to resize a single image to the exact pixels or proportion you specified, you can access ResizeImage.net, it supports JPG, PNG and animated GIF formats, you can even compress your images to smaller sizes without losing quality using the highly customizable options provided, and it's totally free!
No problem, Bakari.
Perhaps most people do think that resizing an image is a deadly simple function, but actually many online image editors and resizers haven't offer the ability to crop and resize an image to the extract proportion or pixels, which is necessary to use an image as your avatars on sites like Facebook, Twitter, LinkedIn, VK, Pinterest, Tumblr and other social networking sites without distortion.
The most popular image editing sites like Pixlr, fotor, befunky do offer this function, however they need you to have Flash player installed, and most of them do not support cropping and resizing the animated GIF format, do not support compress PNG images with transparent background, and do not support the progressive compression method for JPEG images.
Resizeimage.net is simple and does not offer image editing functions, but it's designed for cropping, resizing and compressing images in one step, and we've fixed two errors and now it displays correctly in IE 8, but obviously it works best in the Chrome browser, and we found that the IE users( all versions ) do not like to use online generators and converters, over 90 percent of the users to our sites are using Chrome, Firefox and Safari.
To do it quickly and for free (comes standard with every mac), use sips.
Open a terminal, go to the folder where your pictures are located and type:
sips -Z 640 *.jpg
All jpg files will be converted to 640 x whatever and aspect ratio maintained.
Nice article. I will check out your Automator article. Automation tool for mac os.
A couple of small apps that I have found to do well at resizing images are ResizeMe (free) from Dare to be Creative / Incredible Bee (http://www.creativebe.com) & Downsize ($19.95) from Stunt Software (http://stuntsoftware.com/downs.. (ResizeMe was not listed at the Incredible Bee site, but is available at Apple (http://www.apple.com/downloads.. & other sites.) ResizeMe has a simple drag images onto a palette interface, does batch processing, adds drop shadows, watermarks, & reflections. Downsize also does batch processing & can add watermarks & frames. It also has built-in integration with iPhoto by way of a mini-browser.
Nice article. I will check out your Automator article.
A couple of small apps that I have found to do well at resizing images are ResizeMe (free) from Dare to be Creative / Incredible Bee (http://www.creativebe.com) & Downsize ($19.95) from Stunt Software (http://stuntsoftware.com/downs.. (ResizeMe was not listed at the Incredible Bee site, but is available at Apple (http://www.apple.com/downloads.. & other sites.) ResizeMe has a simple drag images onto a palette interface, does batch processing, adds drop shadows, watermarks, & reflections. Downsize also does batch processing & can add watermarks & frames. It also has built-in integration with iPhoto by way of a mini-browser.
Nice article. I will check out your Automator article.
A couple of small apps that I have found to do well at resizing images are ResizeMe (free) from Dare to be Creative / Incredible Bee (www.creativebe.com) & Downsize ($19.95) from Stunt Software (http://stuntsoftware.com/downsize/). (ResizeMe was not listed at the Incredible Bee site, but is available at Apple (http://www.apple.com/downloads/macosx/imaging_3d/resizeme.html) & other sites.) ResizeMe has a simple drag images onto a palette interface, does batch processing, adds drop shadows, watermarks, & reflections. Downsize also does batch processing & can add watermarks & frames. It also has built-in integration with iPhoto by way of a mini-browser.
thanks for the input
Cool list. I prefer QuickScale from CodingMammoth (see Mac App Store), just 9.99 but good interface and powerful tool for single/batch scaling of images.
Pol, i'll check this one out. I'm always looking for better solutions.
Oh, thanks a lot for sharing this step-by-step ways on how to resize the photos in my Mac. Thank you very much. I am not that of a techie person so I will definitely use this tutorial.
you're welcome Randy!
Cool, Randy. Glad you found it helpful.
Disk Utility underwent quite a bit of change when Apple released OS X El Capitan. The new version of Disk Utility is much more colorful, and some say easier to use. Others say it has lost many of the basic capabilities that old Mac hands took for granted.
While this is indeed true for some functions, such as creating and managing RAID arrays, it's not true that you can no longer resize your Mac volumes without losing data.
We will confess though, that it's not as easy or intuitive to resize volumes and partitions as it was with the older version of Disk Utility. Some of the problems are caused by the clumsy user interface that Apple came up with for the new version of Disk Utility.
With the gripes out of the way, let's take a look at how you can successfully resize volumes and partitions on your Mac.
The Rules of Resizing
Understanding how resizing works in Disk Utility will go a long way toward helping you resize a volume without experiencing any loss of information.
Fusion Drives that have been partitioned can be resized, however, never resize a Fusion Drive with a version of Disk Utility older than the version that was originally used to create the Fusion Drive. If your Fusion Drive was created with OS X Yosemite, you can resize the drive with Yosemite or El Capitan, but not with any earlier version, such as Mavericks. This rule doesn't come from Apple, but from anecdotal evidence gleaned from various forums. Apple, however, does mention that in no case should a version older than OS X Mavericks 10.8.5 ever be used to resize or manage a Fusion Drive.
To enlarge a volume, the volume or partition that is directly after the target volume must be deleted to make room for the enlarged target volume.
The last volume on a drive can’t be enlarged.
The pie chart interface for adjusting volume size is very picky. When possible, use the optional Size field to control the size of a drive segment instead of the pie chart's dividers.
Only drives formatted using the GUID Partition Map can be resized without losing data.
Always back up your drive's data before resizing a volume.
How to Enlarge a Volume Using Disk Utility
You can enlarge a volume as long as it's not the last volume on the drive (see the rules, above), and you're willing to delete the volume (and any data it may contain) that resides directly in back of the volume you wish to enlarge.
If the above meets your goal, here's how to enlarge a volume.
Make sure you have a current backup of all data on the drive you wish to modify.
Launch Disk Utility, located at /Applications.
Disk Utility will open, displaying a two-pane interface. Select the drive that contains the volume you want to enlarge.
Click the Partition button on Disk Utility’s tool bar. If the Partition button isn't highlighted, you may not have selected the base drive, but one of its volumes.
The drop-down partitioning pane will appear, displaying a pie chart of all of the volumes contained on the selected drive.
The first volume on the selected drive is displayed starting at the 12 o’clock position; other volumes display moving clockwise around the pie chart. In our example, there are two volumes on the selected drive. The first (named Stuff) begins at 12 o'clock and encompasses the pie slice ending at 6 o’clock. The second volume (named More Stuff) starts at 6 o’clock and finishes up back at 12 o’clock.
In order to enlarge Stuff, we must make room by deleting More Stuff and all its contents.
Select the More Stuff volume by clicking once within its pie slice. You'll notice the selected pie slice turns blue, and the name of the volume is displayed in the Partition field to the right.
To delete the selected volume, click the minus button at the bottom of the pie chart.
The partitioning pie chart will show you the expected outcome of your action. Remember, you haven't yet committed to the results. In our example, the selected volume (More Stuff) will be removed, and all of its space will be reassigned to the volume to the right of the deleted pie slice (Stuff).
If this is what you want to occur, click the Apply button. Otherwise, click Cancel to prevent the changes from being applied; you can also make additional changes first.
One possible change would be to control the size of the expansion of the Stuff volume. Apple’s default is to take all of the free space created by deleting the second volume and apply it to the first. If you would rather add a smaller amount, you can do so by selecting the Stuff volume, entering a new size in the Size field, and then pressing the return key. This will cause the selected volume's size to change, and create a new volume made up of any free space that's left over.
You can also use the pie chart divider to adjust the size of the pie slices, but be careful; if a slice you wish to adjust is small, you may not be able to grab the divider. Instead, select the small pie slice and use the Size field.
When you have the volumes (slices) the way you want them, click the Apply button.
Resizing Without Losing Data in Any Volume
It would be nice if you could resize volumes without having to delete a volume and lose any information you have stored there. With the new Disk Utility, that isn't directly possible, but under the right circumstances, you can resize without losing data, although in a somewhat complicated manner.
In this example, we still have two volumes on our selected drive, Stuff and More Stuff. Stuff and More Stuff each take up 50% of the drive space, but the data on More Stuff is only using a small part of its volume's space.
We wish to enlarge Stuff by reducing the size of More Stuff, then adding the now free space to Stuff. Here is how we can do that:
First, make sure you have a current backup of all the data on both Stuff and More Stuff.
Launch Disk Utility.
From the right-hand sidebar, select the drive that contains both the Stuff and More Stuff volumes.
Click the Partition button.
Select the More Stuff volume from the pie chart.
Disk Utility will allow you to reduce the size of a volume as long as the current data stored on it will still fit within the new size. In our example, the data on More Stuff is taking up very little of the available space, so let's reduce More Stuff by slightly more than 50% of its current space. More Stuff has 100 GB of space, so we're going to reduce it to 45 GB. Enter 45 GB in the Size field, and then press the enter or return key.
The pie chart will show the anticipated results of this change. If you look closely, you'll notice that More Stuff is smaller, but it's still in the second position, behind the Stuff volume. We have to move the data from More Stuff to the newly created, and currently untitled, third volume on the pie chart.
Before you can move the data around, you have to commit to the current partitioning. Click the Apply button.
Disk Utility will apply the new configuration. Click Done when it's complete.
Moving Data Using Disk Utility
In Disk Utility’s sidebar, select the untitled volume you just created.
From the edit menu, select Restore.
The Restore pane will drop down, allowing you to “restore,” that is, copy the contents of another volume to the currently selected volume. In the drop-down menu, select More Stuff, and then click the Restore button.
The restore process will take some time, depending on the amount of data that needs to be copied. When it's complete, click the Done button.
Finishing the Resizing
Free Photo Resizing Tool
In Disk Utility’s sidebar, select the drive that contains the volumes you've been working with.
Click the Partition button.
In the partition pie chart, select the pie slice that is immediately after the Stuff volume. This pie slice will be the More Stuff volume you used as the source in the previous step. With the slice selected, click the minus button below the pie chart.
The selected volume will be removed and its space added to the Stuff volume.
No data will be lost because the More Stuff data was moved (restored) to the remaining volume. You can verify this by selecting the remaining volume, and seeing that its name is now More Stuff.
Click the Apply button to finish the process.
Resizing Wrap-Up
As you can see, resizing with the new version of Disk Utility can be simple (our first example), or a bit convoluted (our second example). In our second example, you could also use a third-party cloning app, such as Carbon Copy Cloner, to copy the data between the volumes.
Free Picture Resizing Tools
So, while resizing volumes is still possible, it has become a multi-step process that requires a bit of planning before you begin.
Photo Resizing Tool Online
Nevertheless, Disk Utility can still resize volumes for you, just plan ahead a bit, and be sure to have current backups.