If you need to center an object in a Photoshop image, you can use its built-in tools instead of doing it manually. The "Move" tool allows you to move a selected layer to the center of the image. The following steps are also good for a Photoshop-like image editor like GIMP.
Steps
Step 1. Select the layer you want to center on the image
Use the layer selector window to select the layer you want to center.
- If it is blocked, you will need to duplicate it to gain access to it. Press the Ctrl/⌘ Command+J keys to duplicate the selected layer. Go to the How to Unlock Layers in Photoshop article for more detailed instructions.
- If you just want to center the look of a layer, you'll need to use the selection tools and then create a layer from the selection. Right click on the selected part of the image and select "Create layer from selection".
Step 2. Press the keys
Ctrl/⌘ Command+A to select the entire layer.
You will see the dotted checkbox around the edge of the layer.
You can use this same method to center an object in the middle of a selection instead of the middle of the image. Instead of pressing the Ctrl/⌘ Command+A keys to select everything, choose the "Selection" tool to define your own area in the image. By following the process below, the image will be centered on the selected area
Step 3. Click on the "Move" tool
It's in the toolbox in the left corner of the screen, and it looks like a mouse cursor with crosshairs on the side. You can also press the V key to select it.
Step 4. Click on the "Align Vertical Centers" button
It can be found in the toolbar at the top of the window, or in the "Attributes" window that appears below the toolbox on the left side of the screen. This button has a small black triangle icon with a white square in the center and serves to align the selected layer vertically centered.
The location of this button may vary depending on the Photoshop version used, but it should always be present when selecting the "Move" tool
Step 5. Click on the "Align Horizontal Centers" button
It is located next to the "Align Vertical Centers" button, and has a box icon centered above a horizontal black rectangle. This button serves to center the selected layer horizontally.
Step 6. Make manual adjustments
If the object you're trying to center isn't already centered on the layer, you might need to make some manual adjustments.