Resizing smart object to match other smart object's exact dimensions

Hi there

To Match a size of a logo with a dimention of another logo
Select the source smart object (the one with the fixed height).
Press ctrl + T (Windows) or cmd + T (Mac) to enter free transform mode.
the height value displayed in the top toolbar (e.g., "H:300 px").
Select the target smart object (the one you want to resize).
Press ctrl + T (Windows) or cmd + T (Mac) to enter free transform mode.
Click the chain icon between the width and height fields in the top toolbar to unlink them.
In the height

• Use the Info Panel: First, make sure the Info Panel is open (Window > Info). This panel will show you the exact dimensions of any object you’re selecting.

• Select the First Smart Object: Click on the first smart object (the one you want to copy the dimensions from) and take note of its width and height in the Info Panel.

• Select the Second Smart Object: Now, select the second smart object (the one you want to resize).

• Manually Input Dimensions: While the second smart object is selected, go to the Properties Panel and you'll notice the width and height fields. Although they may not be directly editable for smart objects, you can still manually adjust these values. Input the exact width and height from the first smart object based on the dimensions you noted from the Info Panel.

• Match Position (Optional): If you also need to align them perfectly, you can use the Align tools at the top of the workspace or manually position them by holding Shift (to keep proportions) and dragging.

"Normally in Illustrator, I would copy the height of one object and paste it into the height field of another object, but in Photoshop, I've noticed the height and width fields in the Properties panel are not editable for smart objects, so I can't do that."

Select Smart Object layer, press Ctrl + T to enter free transform mode. Right click inside W or H field and change measurement unit to Pixels if required. Select either content of W or H field and press Ctrl + C to copy. Do the same for SO that you want to match dimensions but this time select and paste using Ctrl + V. Let me know wheteher you are able to perform this or at which step you have problem.

You can lay out guides the exact size and snap to them.

Drag out the grid zer0 to an arbitary position, and make horizontal and vertical guides at the zero point as below.

Then new guides to foirm a bounding box the exact pixel size.  

FT will snap to that box, but you might need to hold down the shift key if the aspect ratio differs.

It's difficult to give exact advise without seeing the shape of the SOs, but the general advise I'd give wouldd be to use guides as the free transform will snap to them.  Open, one, or both SOs in their own window by double clicking, and use Image Size (Ctrl Alt I) to see the precise dimension.  You could do this with the larger SO, to get the size. Then open the smaller SO in its own window, and change the canvas size to match the larger SO, and Free Transform to the window bounds.

Does any of that make sense?  If you are worried about loosing image quality, then you can nest the SO, i.e. open in its own window, and make it an SO in that window.