What size should my logo image be for the email signature?
The signature this tool builds always shows the logo 64 pixels wide, with the height scaled to the image's proportions. So a square or nearly square logo works best. Prepare the file at about twice that width, around 128 pixels, so it stays sharp on high-density screens, and keep the file small.
Fixed width, height follows the image
In the code the tool produces, the image tag has a fixed width of 64 pixels and an automatic height. That is deliberate: the fixed width stops a large logo from pushing the whole signature off screen in email programs that ignore image sizes, and the automatic height keeps the logo's proportions so it never stretches. The result is that the logo's own shape decides how it looks.
We worked out the resulting height for three common shapes with the image resizer's locked-ratio calculation:
- A square 512 × 512 logo shows at 64 × 64 pixels, clear beside your name.
- A 1000 × 800 logo shows about 51 pixels tall and stays readable.
- A wide 600 × 150 banner shows only 16 pixels tall, about the height of a line of text, so its detail and wording are lost.
Why twice the width?
Many phones and modern screens use two or more device pixels for every pixel in the layout. If your file is exactly 64 pixels wide, it looks soft and slightly blurred on those screens. A file 128 pixels wide gives the screen enough detail and is still small. Going bigger gains nothing: every recipient downloads the whole file only to show it at 64 pixels.
Preparing the logo step by step
- If your logo is wide, use its symbol or initial rather than the full lockup, or crop it to a roughly square shape.
- Open the Image resizer and set the width to 128 with the ratio locked. A 512 × 512 square becomes 128 × 128, and 1000 × 800 becomes 128 × 102.
- Save it as PNG if it has a transparent background, upload it to your website or store, and copy the direct image address.
- Paste the address into the logo field of the Email signature builder, and compare the preview with another version if you have more than one.
The logo sits beside your details, not above them: on the right in an Arabic signature, on the left in an English one, with 14 pixels of space between it and the text. That is why a tall, narrow logo is also a poor fit: it raises the height of the whole signature.
And if the image is blocked?
Some email programs do not show external images until the recipient allows them. The tool gives the image an empty alternative text, so no odd word or file name appears in its place, and your name and details stay as clear text. For the same reason, never put information in the logo that is not also in the text, such as your phone number.
Common questions
Can I make the logo 100 pixels wide in the signature?
Not in this tool; the width is fixed at 64 pixels in the code. That keeps the signature balanced across different email programs.
Does the file size in kilobytes matter?
Yes, because everyone who opens your email downloads it. A 128 pixel wide file is usually small, and you can compress it further if you like.