P: PS 27.4 Setting the default in Preferences > Units to "inches" is ignored by Canvas Size

Still broken as of 4/22/26. Not a huge deal obviously, but definitely disrupts the workflow when, say, setting up a bunch of odd/custom sizes onto standard size papers 

I’m hoping putting in a reply will get me notified when this is fixed.  I followed the very helpful tip on disabling the ‘modern interface’ and now my change canvas is back to my preferred percent option.  Thank you for the tip.  I do hope that Adobe still fixes this issue, though, since I don’t know what else removing that option might break.  

I just updated to PS 27.5.0 and still have this problem. Mac OS Tahoe 26.3.1

It's tedious to do it fully, unfortunately, but it might be worth thoroughly resetting Photoshops preferences - something lurking there from an old version may be affecting an issue you are observing.

Here's a bit more detail on resetting preferences, because, unfortunately, a simple reset doesn't always do everything :

Perhaps try a thorough reset of Photoshop preferences? 

(read this entire text before acting please)

Unexpected behaviour of Photoshop may indicate damaged preferences, which are saved when Photoshop closes.. Restoring preferences to their default settings is a good idea when trying to troubleshoot unexpected behaviours in Photoshop.

When preferences become corrupt, then various issues can occur.

Here’s some info from Adobe about preferences:

Learn how to access and modify Photoshop preferences and customise according to your frequent workflows

https://helpx.adobe.com/photoshop/using/preferences.html#reset_preferences

According to Adobe, manually removing preferences files is the most complete method for restoring Photoshop to its default state. This method ensures that all preferences and any user presets which may be causing a problem are not loaded. More here: https://helpx.adobe.com/photoshop/using/preferences.html#Manually

The process:

1. Quit Photoshop.
2. Navigate to Photoshop's Preferences folder.
   macOS: Users/[user name]/Library/Preferences/Adobe Photoshop [version] Settings
   Windows: Users/[user name]/AppData/Roaming/Adobe/Adobe Photoshop [version]/Adobe Photoshop [version] Settings
    
   Note: The user Library folder is hidden by default on macOS. To access files in the hidden user Library folder, see How to access hidden user library files.
3. Drag the entire Adobe Photoshop [Version] Settings folder to the desktop or somewhere safe for a backup of your settings
4. Open Photoshop.
    New preferences files will be created in the original location.

You may want to back up your settings and custom presets, brushes & actions before restoring Photoshop's preferences.

Here is general info about that:  https://helpx.adobe.com/photoshop/using/preferences.html#BackupPhotoshoppreferences

And here’s an Adobe Quick Tips link as an aid to overall understanding

https://community.adobe.com/t5/photoshop-ecosystem-discussions/quick-tips-how-to-reset-photoshop-preferences/td-p/12502668

Thanks to Digitaldog for this quick and simple method:

Press and hold Alt+Control+Shift (Windows) or Option+Command+Shift (macOS) immediately after launching Photoshop. You will be prompted to delete the current settings.

You can also reset preferences on quit, if Photoshop is running, by going into General Preferences>General>Reset on Quit.

This action only affects the items found in the preferences dialog box. Numerous program settings are stored in the Adobe Photoshop Preferences file, including general display options, file-saving options, performance options, cursor options, transparency options, type options, and options for plug‑ins and scratch disks. Brushes (and lots of other settings) are not affected by the above instructions for deleting preferences.

You may wish to make a screen capture of the settings in the Preferences dialog to reset them prior to deleting this file. 

Before you reset your preferences, in case of future issues, I suggest you make a backup copy as Adobe may need one to check problematic preferences. 

Quit Photoshop.
Go to Photoshop's Preferences folder

Preferences file locations: https://helpx.adobe.com/photoshop/kb/preference-file-names-locations-photoshop.html\

  [on MacOS see: Users/[user name]/Library/Preferences/Adobe Photoshop [version] Settings

  Note for those on macOS: - Be aware that the user Library folder is hidden by default on macOS. More on that here:

  https://helpx.adobe.com/x-productkb/global/access-hidden-user-library-files.html

  In the Finder, open the “Go” menu whilst holding down the Option (Alt) key.

  "Library" will now appear in the list - below the current user's “home” directory. ]

Now you can drag the entire Adobe Photoshop [Version] Settings folder to the desktop or somewhere safe as a backup of your settings.

Note for macOS:

Preference preservation is affected by macOS permissions,

You’ll need to allow Photoshop ‘Full Disk Access’ in your Mac OS Preferences/Security and Privacy

If resetting preferences doesn't fix your issue:

Go to Preferences > Performance... and uncheck Multithreaded Compositing - and restart Photoshop.

Is Photoshop still hanging? 

Go to Preferences > Performance... click Advanced Settings... and uncheck "GPU Compositing" - then restart Photoshop. 

It may even be time to reinstall Photoshop. 

It’s recommended that you use the Adobe CC cleaner tool to remove all traces first. 

(See above about preserving preferences first, though! It’s worth preserving them unless they are corrupted.)

How and when to use the Creative Cloud Cleaner tool | Advanced steps

https://helpx.adobe.com/creative-cloud/kb/cc-cleaner-tool-installation-problems.html

Uninstall Photoshop BUT make sure to choose the option “Yes, remove app preference”.

Once that process finishes, start the installation process and look into the “Advanced Options”. Uncheck “Import previous settings and preferences” and choose to “Remove old versions”.

neil barstow - adobe forum volunteer, 

colourmanagement consultant & co-author of 'getting colour right'

See my free articles on colour management

Help others by clicking "Correct Answer" if the question is answered.

Found the answer elsewhere? Share it here. "Upvote" is for useful posts

The recent 27.5 release got updated Canvas Size modal, and it has several bugs that affect my workflow, which requires gradual pixel-perfect changes of canvas size in various directions (my units are pixels most of the time).
I use relative changes to canvas size, so ‘Relative to current dimension’ checkbox is ON for me most of the time, and in this case the bugs I get are:

1. Canvas Size modal opens with default values of width and height set to 1 pixel. Should be 0.
2. The width and height inputs do not accept 0 value — it gets reset to 1, meaning if I want to change canvas size in one direction, anyways I’ll get 1 pixel added to the other.
3. It’s not possible to set negative values now, which used to work before, and at times it’s more convenient and precise way to ‘crop’ canvas, rather than using the Crop tool.
4. The values step now is 0,01 pixel, which is meaningless in most scenarios. It used to be 1 pixel, and it should be, as it allowed to use keyboard up and down arrows for quick pixel perfect adjustments.

See attached video demonstrating all 4.

What I discovered later: if I uncheck ‘Relative to current dimension’ checkbox and check it again — I get the right behaviors (except bullet 4 with increment step). Those all are apparently bugs to be fixed.

System:

Photoshop 27.5.0
macOS 26.3.1 
MacBook Pro, 16-inch, 2023

I have the same problem. 

D’oh! LOL that was it!

Uncheck “Relative” in the Canvas size dialog.

Ctrl or Cmd R to show Rulers, then right or ctrl click on the ruler to set your default measurement units. If you choose inches, Canvas Size shoulld default to inches.

Hello all!

For the past version or two Photoshop changed the way a size can be changed. The default used to be that you just say the new canvas size, and it sets to the new number. Now it asks for the difference between the current size and the one you want. Which requires a ridiculous amount of math to get to the exact decimal point you need. There’s gotta be a way to set it back to simply state the desired new canvas size, right?? Anybody know how to do that?

(Also how to default it to be in inches vs. pixels.)

Thanks!

As is always the case, a new poorly-tested, poorly-executed “improvement” is the cause, and the solution is to find where the offending non-improvement can be disabled, followed by disabling, followed by a few curse words about dumb thing Adobe does all the time.