What is the best email signature size? (plus tips)

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If you’re looking to find out what the best size for your email signature is, you’ll find a guide of tips, tricks, and explanations right here!

Nowadays, there’s no disputing that everyone in the workplace needs to know how to compose a proper, professional email. However, there are some things that set others above the rest. Style, tone, and general professionalism all contribute to how your email is going to be received.

Luckily, there is a simple solution that can make your email look ten times better: an email signature.

Why an email signature?

Email signatures are the best things for adding a touch of professionalism when you email clients. They can also help to promote your brand, add convenient contact details, and include links to your social media accounts all in one go!

Here, we’ll be providing you with absolutely everything you need to know about email signatures and how to size and format them so that they look as good as they possibly can.

Email signature size: dimensions

First, let’s discuss the email signature dimensions. You have about 600 pixels width to work with, but email signature width best practices suggest that you should aim for a size of about 320 pixels wide. This is because many email signatures these days are viewed on mobile devices.

For height, it is recommended that you keep it below 200 pixels. This is so that it is easy to scroll through an email chain – especially on mobile.

Essentially, you can make your email signature quite large, but a relatively small one tends to work better on mobile and is more pleasing to the eye.

Example of 320px wide email signature template:

Email signature size: weight

Email signatures may look a certain size but, as we all know, files differ in the actual weight and space they take up. Size in this section refers to the size in kilobytes (KB). Again, the answer to the question, “what is the best email signature size?” is that it should be small.

You don’t want to have your email signature comprising too many KBs. This can actually end up costing you a lot of money because user mailboxes fill up quicker and unnecessary disk space is taken up at a rapid rate.

Rather, files should be smaller or compressed. Aim for as low a KB mark as possible – even when using images.

Email signature sizing for different elements


Email signature image size should take up between 150px – 300px of width. Images typically take the form of a logo or a profile photo, and the height of these will always depend on your company’s branding and design. They may be square, long, or tall.

No matter the design of your logo or added image, make it small but still in line with the rest of your email signature. Images should take up about 30kb of the recommended 150kb total file size for email signatures. File formats should either be JPG, GIF, or PNG.

See also: How to add logo and icon images to an email signature.


The web resolution of your images (image quality) should be very high. It is therefore a good idea to save a 300px – 600px image at 150px – 300px width. Essentially, save a larger image to present as a smaller image size.

This way, your email signature image will look far clearer than it would if the original image was of lower quality. Image resolution is very important for displaying professionalism and clearly presenting your brand image.


Banners are images that show at the very bottom of your email signature. They are typically used to link to your website or to further promote your brand. Your email signature banner size should be a maximum width of 600px and a max height of 100px.

An email signature banner should only be used when necessary, as it can take up a lot of space. When you do use promotional banner images, try to use an oblong, rectangular shape. This looks better on both a mobile device as well as a desktop.

Example of a 600px wide email signature with a banner:

Web fonts

For font size, keep things small and simple. Do not use large fonts or too many fonts as these can be confusing and disruptive to the eye after the size of the previous email.

It is recommended that you use a font between 11px and 13px. Keeping it small and practical enhances readability and allows your recipient a better experience with your email signature.


Although Gmail allows you to use up to 10,000 characters, we recommend that you keep your email signature characters under 5,000. Yahoo also allows 10,000 characters, while Outlook limits you to 5,000.

Too much text can add to the file size of your email signatures. It can also result in your clients finding the amount of text overbearing. Stick to a lower amount of characters and refrain from including lengthy legal disclaimers. Rather, remember to include things like key contact details.

How do you pick the best size for your email signature?

1. Do your research

One tip to keep at the top of your mind before even attempting to start creating your email signature is to do your research. Of course, if you have gotten this far on this post, you are definitely making that move.

Another thing you need to do in terms of research is to do an extensive analysis of your target market. Figure out what attracts your target audience. For example, what kinds of social media platforms do they use? Use this information to incorporate social media icons in your email signature banner. Figure out sizing accordingly.

2. Incorporate your brand

Always remember that the more authentic you are, the better your brand comes across. Incorporating your brand into your email signatures is a great idea because it allows you to further promote your brand image and display the message you want to get across.

In terms of sizing, this is important. Your company logo size is going to determine how your brand presents to a large degree. So, when incorporating your brand into your email signature, remember to keep our sizing tips in mind.

3. Try an email signature software

Still need help figuring out how to size your email signature, or how to create one in general?

Another tip is to try out email signature management software. This type of software can create HTML email signatures for you. It also adds a ton of professionalism and helps you to sign off in the right way. It always picks the best image size, keeps images the correct amount of pixels wide, and ensures the correct dimensions.

Signature management software like Bybrand can do all of this and more for you! We can help you with the size of email signature images, the design, the content, and ways to promote your brand, yourself, and your whole company.

Plus: This tutorial will show you how to resize a column in your email signature. It covers all the steps for successfully resizing a column with the signature editor.

Email signature templates in different sizes

To create the perfect email signature, it is crucial to consider the right size to ensure that it is visually appealing and easy to see on different devices. Below are examples of the three main email signature sizes: 320px, 480px and 600px.

For mobile devices – 320px

These are usually single-column signatures, optionally in the form of text with links. The 320px width is recommended to ensure that your signature is displayed correctly on smaller screens. However, the downside is that it’s not a good idea to create a mobile signature with lots of information.

Signature template for mobile devices.

Signature template for mobile 320px.

Ideal for tablets – 480px

With a width of 480px, you can make the most of the available space. The advantage of signatures of this size is that they work well for both mobile and desktop devices. It holds a good amount of information.

Signature template for tablet, 480px

Email signature template ideal for tablet.

For larger screens – 600px

With a width of 600px, you have more space to work with, especially if you have a lot of information to add. This allows you to include additional elements such as promotional banners, product images or even a larger company logo.

Lawyer email signature with 600px
Lawyer email signature with 600px

Example of a 600px email signature

Final thoughts

In this post, we have covered everything there is to know about email signature sizes: what your images and banners should look like and weigh, what resolution you should aim for, and the fonts and text that your email signature should present.

Whether it be for business emails, external emails, or internal communication, a professional, good-looking email signature is a must for any company. When you email clients, you want to afford them the opportunity to know more about you and your brand and make a great impression on them.

Keep all of these tips and tricks in mind when creating your new email signature, and don’t forget to check out Bybrand and its templates, integrations, and more!

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Create your first email signature with Bybrand

Bybrand offers the ability to generate, administer, and distribute essential email signatures for your employees.

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