To better understand what I want to explain in this article, imagine that you have to make a photo gallery in which all the thumbnails should have the same dimensions, for example 400 pixels width and 300 pixels height. You could use the Automated Web Photo Gallery but it will generate its own HTML or Flash content and maybe you don’t want that. Keep in mind that you must maintain image quality so resize image proportionally it’s the best solution.
Resize image in Photoshop proportionally
1. Open the picture in Photoshop, fastest way: CTRL+O.
2. Double-click on the layer to unlock it.
3. Press CTRL+T to enter into the Transform mode.
4. Activate the Maintain Aspect Ratio on the Properties bar:
5. In the width box put 400 pixels. You should notice that the height changes also so the picture resizes proportionally, without quality loss. It’s important to remember here that if you put the value 400 into the width and the value in the height box is lower than 300 pixels then it’s not good. The values of the both dimensions must always be equal or above the wanted dimensions or you won’t be able to crop it accordingly. If by any chance, after you have entered the value into the width and the height shows a smaller number than it should, then try the other way around. Put 300 in the height and the width should be bigger than 400 pixels. After you have modified the size hit enter to apply the effect.
Other way to do all this, even easier would be to open the picture, then go to Image – Image Size and in the window that appeared, check the Constrain Proportions box and then fill in the width or height with the dimension you want. Remember to always make sure the dimensions are larger or equal to the ones you want. I didn’t present this method first because I wanted you to know how the Maintain Aspect Ratio works too.
Resize image in Photoshop at specific dimensions
There are in fact 2 ways of doing this: either using the Rectangular Marquee Tool or the Crop Tool. I will present both of them.
Rectangular Marquee Tool Method
1. Activate the Rectangular Marquee Tool on the Toolbar or press M. Activate New Selection on the Properties Bar, Select Fixed Size and enter the desired values in the width and height boxes, like in the picture:
2. Click on the picture and you will see that a dotted rectangular appears. Drag it and make sure you fit it on the image, so that it captures its center. Try to zoom in to see if you placed the rectangle as it should. If you don’t do it good the picture will have other size.
3. Go to Select – Inverse or press SHIFT+CTRL+I and then press Delete. Now you have the picture at the wanted size, without quality loss. Press CTRL+D to get rid of the dotted rectangles.
Crop Tool Method
1. Activate the Crop Tool on the Toolbar or just press C.
2. Enter the wanted dimensions int he width and height boxes, on the Properties bar and set the resolution to 72.
3. Now drag the crop rectangle on the picture. It doesn’t have to be perfect since it will always crop the size that you asked for. After you finished, press Enter or double click on it.
In conclusion, if you want the fastest and easiest way to resize images in Photoshop at specific dimensions and without quality loss, you should open the image, select from the Image menu – Image Size and fill in the dimension after checking the box with Constrain Proportion, as I explained to you above. Then use The Crop Tool Method.
And so the resize image task in Photoshop is complete and successful: