Best practices for email images: Sizes, formats, and embed

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When it comes to email marketing, understanding the images in email best practices can make a world of difference. Regardless of the type of email you’re writing, the right images can enhance your message and engage your audience. 

That being said, there’s more to consider than picking a pretty email picture. You need to think about size, format, and how you embed these visuals into your emails. This article explores this and gives tips on how to make your emails visually appealing and effective. So, let’s get started.

Best practices for using images in emails

As you plan your email marketing campaign, you’ll want to familiarize yourself with the best practices for using images in emails. Sticking to them will help you keep your emails looking professional and appealing to your readers. 

Here are the top things you need to know about using images in your emails:

• Ensure image quality: Always use high-resolution images that align with your email’s message. Poor-quality or pixelated visuals can harm credibility, while crisp, clear images increase engagement and create a professional impression.
• Pick an optimal image file size: To optimize load time and deliverability, keep image file sizes under 100KB. Larger images can slow down email load times, leading to frustration and reduced engagement from recipients.
• Use alt text description: Use descriptive and relevant alt text for each image to ensure accessibility for visually impaired users. Alt text also helps in cases where images don’t load properly.
• Optimize email images for all devices: Many people read emails on their phones, but desktop or tablet users shouldn’t be forgotten. Ensure you optimize the images in your emails to appear as intended, no matter which device the recipient views the content on. Using responsive email templates will guarantee your emails show up looking their best.
• Always consider the text-to-image ratio: Avoid using too many images compared to text, as this is one of the spam filter triggers. A good rule of thumb is a 60:40 text-to-image ratio. Too many images or too little text may mean your emails land in a spam folder. 
• Select the right image format: Stick to common image formats like JPEG, PNG, and GIF. JPEGs work well for photos, while PNGs are ideal for images with transparent backgrounds. GIFs can add a fun, interactive element but should be used sparingly.
• Maintain an overall consistency: Each email you send should reflect a cohesive style. While layouts may vary, design elements such as image styles, colors, header sizes, and email fonts should remain consistent to reinforce your brand identity.

What is the best image size for email?

Are you wondering, “What size should email images be?” Although the ideal email marketing image size for email can vary, there are guidelines to help you keep them looking crisp and clear on any device. You want to choose high-quality images that fit your brand and maintain consistency across the emails you send.

Consider the type of image you’re including in your email. Is the image in square, landscape, or portrait aspect ratio, and is it a product image, header, or infographic? This affects how the image loads and appears on the screen. Here are some general recommendations:

• Full-width header images: The ideal size would be 600-650 pixels wide and 200-300 pixels high. This ensures the image looks great across devices and doesn’t overwhelm the content.
• Smaller in-body or product images: The recommended size would be 300-400 pixels wide and 200-300 pixels high. These images should support your main message without dominating the layout.
• Thumbnail images: Opt for 100-200 pixels wide and 100-200 pixels high for small images or icons. They work well for previews without taking up much space.
• Aspect ratio considerations: Stick to an aspect ratio of 16:9 or 4:3. This will avoid images looking stretched or squished.
• Mobile optimization: Ensure your images scale well for mobile with widths around 320-480 pixels and corresponding heights. This keeps them responsive and user-friendly on small screens.

It might take a few tries to get the size of your email image right, but once you dial it in, you can use the same template again and again to ensure your email images are appealing and your emails get high engagement rates.

What is the best image format for email?

Choosing the right image format can significantly impact your email’s appearance and performance. Let’s break down the most common formats:

JPG format

JPG (or JPEG) is a great choice for photos and colorful images. It uses lossy compression, which reduces the file size while still maintaining good quality. That’s why JPGs are awesome for emails where you need things to load quickly. On the downside, they don’t support transparency, and the quality might decrease slightly if you edit them too much.

GIF format

GIFs are great for simple graphics, animations, and images with a few colors. They can have transparent backgrounds but remember, GIFs are limited to 256 colors, so they’re not the best choice for detailed images or photos.

PNG format

PNGs are great because they keep all the details of an image without losing any quality. They also support transparency, making them perfect for logos, icons, and text-heavy images. They work well if you want to maintain high quality in emails, but just a heads-up — they’re usually larger files than JPGs.

What is an embedded image in an email?

An embedded image in an email is a picture placed directly within the email body. It displays automatically when the recipient opens the email, without needing to download the image separately. 

Difference between attached vs. embedded images

The primary difference between attached and embedded images in emails is how they’re displayed and accessed. Attached images are sent as separate files along with the email. Recipients must download these attachments to view them, which can be useful for preserving the original size and quality of the image. Attachments are ideal if you’re sending high-quality photos or documents that the recipient might want to save or print. 

On the other hand, embedded images are part of the email’s HTML code, meaning they pop up automatically in the email body when you open it. This can make the email more visually appealing and engaging without extra steps for the reader. Embedded images are particularly great for marketing emails, newsletters, or where you want to grab attention right away.

But there are some downsides — embedded images can make the email larger, which might slow down load times and affect delivery. Plus, some email clients block them by default for security, so the recipient might have to turn them on manually. Knowing these differences can help you decide which method to use based on what you’re trying to achieve and what the reader might prefer.

How to embed images into email

So, you have your beautiful images ready. Now it’s time to add them to your email. That’s called embedding, and knowing how to do it correctly will save you a headache. Let’s take a look at how to embed images in emails with popular email providers such as Gmail and Outlook, as well as Omnisend’s email builder. 

Embedding email images with Gmail

Follow these steps to embed an image directly into a Gmail email:

1. Go to your Gmail account
2. Click on the Compose button on the upper left side of the screen
3. Click on the Insert Photo button at the bottom of the message window (it looks like a box with hills)
4. From the Insert Photo page, select the photo you want to use by clicking the Upload option or click on Web Address (URL) to use an image from the internet
5. Click on Insert at the bottom of the screen once you have your photo uploaded, making sure you have your cursor in the email where you want your image to appear
6. To resize your image, click on it and use the boxes to shrink or expand it — you can edit the alt text by clicking the option at the bottom of the selected image

Embedding email images with Outlook

Use these steps if you want to embed an email image in an Outlook email:

1. Go to your Outlook email account
2. Click on the New mail option from the left corner
3. Place your cursor in your email where you want your image to appear
4. Click on the Insert button in the toolbar at the top of the new email
5. Choose Pictures from the menu
6. Select photos from This Device, Stock Images, or Online Pictures
7. When you have your image, click Open
8. Resize the image using the boxes in the corners

Embedding email images with Omnisend

Here’s how to embed images or GIFs in your emails with Omnisend:

1. Go to your Omnisend account, start a new email campaign, and select your preferred email template
2. Once you’re in the email builder, click on the Quick add button at the top of your library
3. Drag the Image element to where you want the image or GIF to appear in the email
4. On the right side of the screen, click Select file to choose the GIF or image you want to add
5. Choose to upload an image from your device or get one from the internet using a URL
6. Insert the image, and you’re all set

Personalizing images for email marketing

Personalizing email marketing images can significantly enhance your connection with subscribers. By tailoring visuals to individual preferences, you can create memorable experiences that increase engagement and drive conversions. Here are some essential tips for effectively personalizing images in your email campaigns:

Use names in images

Incorporating the recipient’s name into images is one of the easiest ways to personalize your email marketing. This simple touch can make your communication feel more intimate and engaging, surprising readers with a level of personalization they might not expect from a marketing email. Services like NiftyImages allow you to seamlessly add names to images.

Customize location-based content

If your goal is to encourage readers to visit a physical store, consider sending them a custom map that highlights the nearest location based on their geographic data. This strategy not only provides valuable information but also emphasizes your brand’s commitment to serving the local community. Personalizing content in this way can lead to increased foot traffic and stronger customer relationships.

Tailor product recommendations

Leveraging a recipient’s purchase history or browsing behavior can enhance the relevance of your email marketing. By showcasing products that align with their interests, you can increase the likelihood of conversions. Automated product recommendation emails can highlight items that the recipient may have previously shown interest in while also suggesting alternative options. This approach not only boosts sales but also demonstrates an understanding of customer preferences.

The message below invites the recipient to view products they may have shown interest in previously, all while suggesting a few alternatives in case they change their mind:

Utilize automation tools

Take advantage of automation tools like Omnisend to streamline the process of creating personalized images for email campaigns. Features such as the Product Recommender allow you to automate the tedious work of generating tailored product suggestions, making it easier to engage your audience effectively.

Additionally, Omnisend’s Brand Assets feature lets you import your brand’s logos, colors, and fonts, ensuring consistency in your marketing materials while saving you time and effort.

By implementing these strategies, you can enhance your email marketing campaigns and create more personalized experiences for your subscribers, ultimately driving higher engagement and loyalty.

Creating HTML emails with images using email service providers

This article covers only HTML emails that are sent via email service providers for promotional purposes. It aims to answer questions about how to send HTML emails with images and how to embed images in HTML emails.

These emails include: 

• Email layout
• Text formatting
• Coupons
• Images
• Rich media elements

When building a beautiful HTML email, marketers use email service providers such as Omnisend. These platforms have email-building tools — ready-made studios for marketers so they can design an email and include images they want. 

Usually, these email builders apply a drag-and-drop method so you can embed your image into the email by dragging the necessary content blocks and uploading the image you want.

See below an example of the Omnisend Email Builder:

There are email builders that offer built-in image editing functionality. These allow you to edit images and adjust them to your email design in the email content editor.

For example, within the Omnisend platform, you can use the Adobe Creative Cloud Connected image editor. On Omnisend, image sizes can be edited this way, too. Since you don’t need to use any other apps for images, building better-looking newsletters becomes a lot quicker.

Using email background images

Most ESPs have the functionality of adding background images to promotional newsletters.

On the one hand, using background images can help your email stand out from other emails. It also gives more email design opportunities.

On the other hand, not all email clients display these backgrounds equally. So, for some recipients, your email could be viewed differently than you intended.

Whether it’s worth using it or not, you can decide after analyzing your audience and its email clients in your Google Analytics account.

Do emails with images perform better?

About two-thirds of people prefer emails that are mostly visual. Emails that include images usually do better than those that are just text. Visuals grab attention and make the content more fun and easy to understand, as well as being able to get messages across quickly. 

Just keep in mind that it’s important to strike a good balance between images and text — too many images can be overwhelming and may slow down loading times. Mixing both can amp up the effectiveness of email campaigns, leading to more engagement and better results.

Why you should never send image-only emails

Sending emails that only contain images might seem visually appealing, but it comes with significant drawbacks that can harm your email deliverability and user experience.

Deliverability issues

Many email clients are cautious with image-only emails, often flagging them as spam. This is because image-heavy or image-only emails are commonly associated with promotional content, which spam filters are designed to catch. 

As a result, your emails may end up in the spam folder, severely limiting their reach. For better results, it’s crucial to maintain a balance between text and images in email marketing. You can read more about email content for better deliverability to ensure your emails land in the inbox.

User experience

Not all users will have images automatically enabled in their email settings. Some email clients block images by default, which means recipients may only see a blank email, so your message gets lost entirely.

Additionally, image-only emails pose accessibility issues for visually impaired users who rely on screen readers. Since these tools can’t interpret images, they won’t be able to convey your message unless alt text is included, and let’s face it — you can’t fit an entire email message just in the alt text. 

A balanced mix of text and images ensures your email is readable and accessible to all users, improving engagement and conversion rates.

How to find email images

Now that you understand the importance of using images in email marketing effectively, you can start looking for images to integrate into your next campaign. Some images will come with restrictions for certain kinds of use. However, there are a variety of ways to find images that are completely free to use for marketing purposes.

Use stock images

Stock images are the simplest way to add images to your marketing emails, and they’re available on a number of sites. With millions of images at your disposal, you should be able to find exactly what you’re looking for. You can also edit stock images by cropping, adding text, adjusting colors, and more.

People often think of stock photos as generic, but they can also look just as authentic as a picture taken by your team. For example, you could look for a stock image that features an everyday person rather than a model. The first image below is much more natural than the second, which clearly looks like a stock photo:

Remember to double-check that an image is free for commercial use before putting it in an email.

Take your own photos

Stock images are perfect for some occasions, but they aren’t as useful for product launches or other things directly related to your brand. In these cases, it may be easier to take photos in-house, especially as high-quality cameras become more prevalent.

Audiences often look for personal connections. Consider using pictures of people in your organization to introduce readers to your team. Taking photos yourself opens up a variety of engaging opportunities. These aren’t available with other options, such as stock images or AI-generated content.

For beautiful, high-quality images of your products, you may want to use a portable photo studio.

Use AI technology

Using AI technology in your email marketing campaigns can give you an edge and help you automate your process so you get better results in less time, especially when it comes to images. With AI image tools, you won’t have to spend hours searching through stock photos or other images to find the ideal email picture. 

Here are some AI image apps that can help you create stunning visuals:

• Microsoft Designer: This tool uses the DALL-E 3 model to generate high-quality images from text descriptions. It’s user-friendly and versatile, making it ideal for creating custom images for various projects. 
• DeepAI: DeepAI’s image generator converts text descriptions into images using advanced machine learning algorithms. It offers multiple styles and customization options, allowing you to create unique visuals tailored to your needs. 
• MidJourney: Known for producing some of the best AI-generated images, MidJourney excels in creating detailed and artistic visuals. It’s particularly popular among designers and artists for its high-quality outputs.
• Adobe Firefly: This tool integrates AI-generated images into photos, providing a seamless way to enhance your visuals. It’s great for those looking to combine AI creativity with traditional photo editing.

Creating images with AI is pretty simple — you input a description of what you’re looking for so the app can then generate image options for you to choose from. 

Creating a consistent brand image is another benefit of using AI technology for your email marketing. AI tools can learn what works best for your brand and keep those details straight, taking the pressure off you.

Image size for email signature

Since we’re on the topic of images in emails, you may also want to add one to your signature.

Incorporating an image into your email signature can add a unique touch to your messages without detracting from the overall content. However, if the image is too large or too small, it can appear unprofessional and messy. Since most users read emails on their phones, it’s essential that email marketing pictures display well on all devices.

Email services respond to oversized images in a variety of unpredictable ways. For example, they might shrink the image to the dimensions of the screen. They may also shrink the entire email or expand the message so that users can scroll across the image. With that in mind, your signature needs to fit the dimensions of each screen.

If you want an image in your email signature, try to keep it as small as possible. While there isn’t a strict rule for image size in email signatures, it’s best to use images that are no more than 150 pixels tall and 300 pixels wide.

Remember that file size is just as relevant as the size of the image itself. Large files can take a long time to download, especially on poor connections.