Email newsletter images: formats and setup

Your newsletter looks right on your computer, but the images may be blurry, slow to load, or missing for some readers. A file that works in a design app does not always work well in an email.

Prepare images to match the newsletter layout, choose a format that suits the content, and check how the message looks on a phone. The Image Converter can convert common image formats in your browser, without uploading your files.

Prepare images for your newsletter

1. Check the image area in your newsletter template. Note its displayed width and whether it fills the content column or sits beside text. If the layout has a 600-pixel-wide image area, a source image around 1200 pixels wide can look sharper on high-density screens, but it will usually take more storage than a 600-pixel version.
2. Keep an untouched copy of each original. Make separate newsletter versions so you can resize, crop, or convert them without losing the source file.
3. Choose the format before you convert. Use JPG for photographs, PNG for artwork that needs transparent areas or crisp edges, and GIF only when you need simple animation and have checked that it works in your target email clients. If the file is in an unsuitable format, open the Image Converter, select the images, and convert them to a suitable format.
4. Add the converted images to your newsletter editor, then preview the message at desktop and phone widths. Check that images fit the layout, text around them still reads well, and each image has useful alternative text in the editor.

Converting a file changes its format, not automatically its dimensions or visual quality. If an image is too wide, crop or resize a copy using an image editor or the newsletter platform before adding it.

Which image format should you use?

JPG for photographs

JPG works well for photos because it can make them much smaller than an uncompressed image. It uses lossy compression, which means some image detail is discarded to reduce file size. Avoid repeatedly editing and resaving the same JPG, since each new save can reduce quality. Start with the original photo and export a newsletter copy.

PNG for graphics and transparency

PNG keeps sharp edges and supports transparency, which is useful for a logo or an illustration with a transparent background. It can be much larger than JPG when used for a photograph. If the image is a photo with no transparent areas, try a JPG copy and compare the appearance and file size.

GIF for simple animation

GIF can contain animation, but support and playback behavior vary between email apps. Some readers may see only the first frame, and large animations can slow loading. Keep the first frame understandable on its own, and use a still image if motion is not essential.

WebP, BMP, ICO, or TIFF files

These formats can be useful in other contexts, but they are not a dependable default for an email message. Support varies between newsletter tools and email apps, and some formats are intended for icons, editing, or print workflows rather than broad email delivery. Convert a copy to JPG or PNG if the newsletter editor rejects the file or recipients cannot see it.

How to fix common newsletter image problems

1. Reduce an oversized image. A very large photo can make a message slow to load, especially on a mobile connection. Resize it to suit the image area in the template, then export a compressed JPG if it is a photograph. Check the finished file size before adding it.
2. Use a larger source for a blurry image. If a small image is stretched across a wide column, the newsletter cannot restore the missing detail. Replace it with a larger original or use a smaller display area. Do not expect changing JPG to PNG, or changing the file extension, to add detail.
3. Check transparency against the email background. A transparent logo can look different on a colored background than it did in your design app. Preview it on the actual newsletter background. If the background must be fixed, export a copy with that background included.
4. Give every important image alternative text. Some readers block images, and people using screen readers need a text description. Add concise alternative text in the newsletter editor. If the image is decorative and the editor supports empty alternative text, leave it empty so it does not interrupt reading.
5. Do not put essential instructions only in an image. Text embedded in a graphic may be too small on a phone, may not resize cleanly, and may be unavailable when images are blocked. Put the key information in the email body as live text, then use the image to support it.
6. Check a rejected or missing file in the editor. Convert an image copy to JPG or PNG and add it again. If the editor accepts the file but the image is absent in a test message, check the newsletter platform's image hosting and sharing settings, then send another test.

Check what readers will receive

An image in an email is usually loaded from a web address managed by the newsletter service, rather than read from a file on your computer. The service may host the image when you add it to a campaign. Converting a file does not upload or publish it by itself, so finish by checking the message preview and sending a test email to an account you can view on a phone.

Keep a readable version of the message for people who have images turned off, and check the newsletter in more than one email app when the campaign matters. The Image Converter runs in your browser, and files you open remain on your device.