Are your email signature images changing size or showing much larger when you install the signature in your email client?
The most common reason for email signature images changing in size is because the image resolution (in DPI) is not set to 72 DPI, or 96 DPI for older versions of Outlook (2016 and earlier).
To fix this, you will need to use an image processing tool such as Photoshop to change the DPI setting on the image.
Let’s take a look at what DPI is and how you can fix this issue.
DPI is primarily used to determine the quality of a document which is going to be printed. However, some email clients, mainly Outlook and Apple Mail use DPI to measure the resolution of images, instead of simply using the height and width of the images.
Image DPI Recommendations for Email Signatures
In order for the images in your email signature to display correctly, you will need to use the following DPI settings depending on which email client you’re using.
- If you’re using older versions of Microsoft Outlook (2016 and earlier), the DPI of the image should be 96 DPI.
- For all other email clients, the DPI of the image should be 72 DPI.
If you have an image in your signature that has a DPI of lets say 300, the image will probably look very big.
How to Check the DPI of Your Images
The simplest way to check the DPI of an image in Windows is to right click on the image > Properties > Details tab, and check the DPI value.
Note: This method only works on some image types and will not work on PNG images.
You can also check and also change the DPI of an image using almost any image processing software, such as Photoshop.
How to Change the DPI of an Image Using Photoshop
Open your image in Photoshop.
Click on Image > Image Size.
In the Resolution field, enter the new DPI value that you want to use:
- 96 DPI for older versions of Outlook (2016 and earlier)
- 72 DPI for all other email clients
Ensure that the measurement is set to “Pixels/Inch” and Resample: Automatic is ticked.
Save your image and use it in your email signature.
Now that the DPI has been changed, this should stop it from scaling up in size.