Aspect Ratio Calculator for Mac — major update with image preview, export, ratio packs, themes, and menu-bar Quick Ratio
Hi everyone — I’m the developer of Aspect Ratio Calculator, a native Mac utility for calculating aspect ratios and preparing exact-size image assets. Problem A lot of image-sizing work is annoyingly repetitive: calculate the missing width or height, keep the ratio locked, resize to an exact final size, avoid stretching, preview whether the image will fit or crop correctly, then export or copy the right values for web/design/dev handoff. Aspect Ratio Calculator is built for that middle ground between “too basic” and “way more app than I need.” It’s useful for websites, social posts, app assets, thumbnails, product images, real estate/MLS images, presentations, documentation, and client work. The new version adds Drag in an image and inspect the original size Calculate missing width/height while preserving proportions Resize to an exact final frame without distortion Fit Inside, Fill & Crop, and Keep Scale modes Preview the output before exporting Export PNG, JPG/JPEG, TIFF, and supported HEIC/HEIF Curated exact-size presets / ratio packs Workspace themes, including Blueprint Dark and branded themes Quick Ratio in the Mac menu bar Copy output for CSS, HTML, Tailwind, Markdown, print, QA, app dev, marketing, and other handoff formats Searchable Help and a first-run walkthrough Localization in English plus 18 additional languages Comparison Compared with Preview, this is more focused on ratio math, exact-size workflows, presets, frame fitting/cropping, export preview, and copy-ready production output. Compared with Photoshop, this is intentionally smaller and faster. It is not trying to be a full image editor. It is the utility you open when you just need the dimensions, ratio, preview, export, or developer handoff values to be correct without launching a heavyweight editor. Pricing Free download with core ratio calculation and basic image/export tools. In-app purchases Aspect Ratio Pro: $9.99 Aspect Ratio Pro Family: $14.99 Workspace Theme & Ratio Pack: $4.99 Pro Ultimate: $14.99 Pro Ultimate Family: $19.99 Optional support/tip purchases: Coffee $2.99, Latte $9.99, Double Shot $19.99 Current discount Pro, Pro Family, Pro Ultimate, and Pro Ultimate Family are currently discounted by $5.00 vs their normal price. Pro Ultimate includes the full Pro feature set plus the Workspace Theme & Ratio Pack in one purchase. Pro Ultimate Family includes the same bundle with Family Sharing support. Pricing is designed so there’s no penalty for starting smaller and upgrading later — buying separately or upgrading later should work out fairly rather than punishing early users. Mac App Store link: https://apps.apple.com/us/app/aspect-ratio-calculator/id498701237
Collected discussion
New version coming soon! We're going to be submitting a new version of the Mac App Store shortly. Here's the internal notes about the changes being made. MAS What's New Draft Aspect Ratio Calculator now gives custom ratios and exact-size presets a clearer home. The Ratios settings tab has a real category manager, so Pro users can create, rename, and delete preset categories while keeping the underlying ratios safe. Ratio pack browsing is also smoother, search can reach across the pack library, and export naming is more predictable when dragging or saving images. User-Facing Changes Added custom category management to Settings -> Ratios / My Presets. Users can create and rename preset categories from the Ratios sidebar. Users can delete a category without deleting its ratios; affected presets move back to the uncategorized/all-presets view. The custom preset editor can choose from existing categories instead of requiring users to retype category names. Imported Workspace Ratio Pack presets now register their pack category in My Presets, preserving more of the curated pack organization. Workspace Ratio Pack search now searches the full pack catalog when a query is entered, rather than only the currently selected pack group. Workspace Ratio Pack cards use indexed import-state lookups to reduce repeated scans while filtering and scrolling large pack lists. Exported and dragged image filenames are based on the original source filename plus output dimensions by default, avoiding generic names such as Dropped Image or PNG image when a real filename is available. Export filename handling avoids duplicate extensions such as .png.png. Dragging an exported image back onto the app is ignored as an app-generated drag, avoiding accidental reloads of the just-exported image. The walkthrough window opens at a more reasonable size on very large displays. Theme cards keep preview artwork clear, show access/category badges under the theme name, and restore the descriptive theme copy. Ratio picker rows are easier to click reliably in the main window and Quick Ratio window, with preset selection applied immediately before the popover closes. Settings -> Copy separates Saved Formats controls from catalog categories and avoids repeated recipe catalog scans while switching categories. Settings -> Copy now supports user-managed Saved Format categories. The sidebar + and - controls create and delete saved-format categories, while custom format creation remains an explicit editor action. Saved copy formats can be assigned to a custom Saved Format category, renamed with the category, or moved back to uncategorized Saved Formats when a category is deleted. Quick Ratio can be set to open at login from Settings -> General. Frame Placement zoom now has -, +, and 100% controls for faster reset and inspection. Settings windows no longer manually jump after macOS places them. The big deal? Really, this new version will be able polish and ensuring things work the way they should. I'm going to continue to iterate on this app to make it smarter, more beautiful, and faster to edit your images for whatever project you're working on. If the app is helpful to you, we'd definitely love a review! If you're unhappy with it, please take a moment to reach out and share your thoughts so we can improve the app.
Looks like a great program.
Does this work with videos too?
does the menu bar quick ratio let you save your own custom ratios, or only the built-in packs? i work with a lot of 4:5 and 21:9 stuff and having those one click away would be huge
Yup. You can save your own ratios. Plus, there's a built in search feature too!
Slightly unrelated question, but is the only way to create a Reddit post with a carousel image gallery that displays a preview image in the main feed to use the Reddit app as opposed to a web browser? I submitted my first post in this community today and blew it because the app screenshot didn't appear in the main feed. WRT the app: I'm a photographer, creator of websites, and semi-serious user of Instagram so I can see the value in an app like this. Does it support batch processing of multiple images?
Batch processing is on the short-term roadmap.
As for Reddit… you need to select the text & image option when you post. They’re like little tabs above the title box.
The image preview is the feature that makes this actually useful rather than just a math shortcut. Calculating ratios without seeing the result means nothing until you drop it into your layout. One thing worth adding to the roadmap: a crop overlay mode where you drag the calculated ratio directly over the source image to preview the crop before committing. That would close the loop between the calculation and the actual use case, which is almost always 'will this fit without distorting' rather than the raw numbers themselves.
We have this.. If you choose "Resize to Frame" then "Keep Scale" you can set the output size, while selecting any piece of the original image. So, in this case, the original image size was 1672 x 941 px, and we wanted a 1000px wide image max. It already knows that the height needs to be 563px, and it'll adjust the DPI as needed to fit the selection into that new max size.. It's my absolute favorite feature of the app!
From the next version -- it hopefully makes the feature a bit more clear. But, the existing version in the MAS already does this -- we're just making it more user friendly to discover the feature 😄
Just bought the app. Is there a way to stop it renaming the output file or setting the output name in the app?
Thanks so much for your purchase! That should be changed in the next version. It was on the list already :) Edit: I knew I addressed this, but it wasn’t working. There was another issue of how macOS told us the filename from a drag/drop.. anyways, it’s now fixed and customizable in settings. It’ll be in the next version once Apple approves it.
Nice I’ll try check it out today
I struggled with aspect ratio for my chrome extension demo shots, this’ll help me heaps
Genuine question, I don't wanna offend, but don't you think that a 6 options paywall is way too much for an app that resize images? I'm curious of this choice. is it working?
Happy to answer.. The main app is free. Use it forever, and pay $0. Prior to this release, it was a much smaller/simpler app, and it was a paid app as opposed to a freemium app as it is now. There are many options available as some people may decide they only want one piece of the app vs. another; and even though it's only a few bucks, it makes the app accessible to more people. Also, the app is over 14 years old! It was originally released on April 2012. So, we have legacy purchasers who get core features while being given the opportunity to help support the app again and add on some very cool new features that were definitely not in the original design.
This will be such a big help for creating app store screenshots!
There's built-in ratios for most major websites (like Appstore Connect) so it knows the sizes you need to submit already! Plus, it can adjust the image AND canvas size at the same time so you can choose any area of an image, and constrain it to a particular ratio while also specifying an output size. It's really useful for so many uses!
I’m not sure I get it, if I want a specific sized photo do I have to type it in, and the app will automatically take screenshots of that size?
Totally fair question — no, it doesn’t take screenshots. The app is for working with an existing image. You drag in a photo, choose the final size you need, and it helps resize/export it to that exact size without stretching or guessing. So for example, if you have a photo that’s 4032×3024 and you need a 1200×630 website/social image, the app shows how it will fit, crop, or scale before you export it. It’s more of an “make this image the exact size I need” tool than a screenshot tool.
is this discount over as it current shows $20 for pro ultimate family
No, the full price of the most expensive version will be $25. However, it is 100% free to download and use the core functionality—forever!
$20 license to do math?
It's free to do math. There is no cost to download or use the app. If you want to use the more advanced features, and you feel the convenience in the app is worth it, you can purchase the pro version for $9.99.