The short answer
An email banner generator is a tool that creates the header or promotional image at the top of an email from a template, your brand colors, logo and copy. Build the banner at your email's content width, commonly around 600 pixels, saved at double size for sharp screens. Keep the file small, add descriptive alt text and put key text in live HTML.
On this page
- Email Banner Sizes and Specs
- How Email Banners Affect Deliverability
- Accessibility Rules for Email Banners
- What to Look for in an Email Banner Generator
- Which Emails Should Carry a Banner
- Email Banner Copy Templates
- Banners vs Linked Visuals in Sales Email
- Make an on-brand visual for one prospect in three steps
- FAQ
Key takeaways
Around 600 pixels wide: Many email layouts sit near 600 to 640 pixels wide. Save at double size and display at full width.
Small files, live text: Keep images light and put the key message in real text, so it survives when images are blocked.
Alt text is required: Some clients, including classic Outlook, block external images by default. Alt text is what those readers see.
No banners in cold email: Banners belong in newsletters and customer email. One-to-one sales email should look like one person wrote it.
Email Banner Sizes and Specs
Get the specs right before you pick a generator. There's no formal standard for email image sizes, but these conventions keep banners sharp, light and readable across the major clients.
| Spec | Common practice | Why |
|---|---|---|
| Width | Your content width, often around 600 to 640 pixels | Fits most desktop reading panes without scrolling |
| Saved size | Twice the display width, e.g. 1200 pixels for a 600 pixel slot | Sharp on high-resolution screens |
| Height | Short, so live text shows in the preview pane | Readers decide fast; a tall banner pushes the message down |
| File size | As small as quality allows | Faster loading, especially on mobile data |
| Format | JPG for photos, PNG for logos, flat color and text | Each keeps its content sharp at a smaller size |
| Animation | GIF, with the message in the first frame | Some Outlook versions show only the first frame |
Width is a convention, not a law. Email testing firm Litmus has called the fixed 600 pixel rule a myth and recommends fluid layouts capped with a max width. Either way, your banner should match whatever your template's content width is.
How Email Banners Affect Deliverability
Banners don't send mail to spam on their own, but they change how your email reads. Filters and people both look at the balance between images and text, and at signals that a message is a bulk send.
- Image-only emails look like ads. Pair every banner with real text that carries the full message.
- External images can be blocked. Classic Outlook blocks automatic picture downloads by default, according to Microsoft's support documentation. Readers see alt text and an empty box until they click.
- Hosting matters. Serve images from your email platform or your own reputable domain, not a random file host.
- Heavier mail loads slower. Compress every image, and avoid stacking several banners in one email.
- Cold email is different. First-touch sales emails should look personal. Our cold email best practices checklist covers the rest of the deliverability basics.
Accessibility Rules for Email Banners
Design for the reader who can't see the image. That includes people using screen readers and anyone whose client blocks images.
- Write alt text that carries the message. Describe what the banner says, not what it looks like.
- Never put the only copy of key information in an image. Dates, prices and calls to action belong in live text too.
- Check color contrast. Light gray on white disappears on a phone in sunlight.
- Test dark mode. Some clients invert colors. Logos with transparent backgrounds can vanish on dark themes, so add a subtle outline or use a solid background.
- Make buttons real buttons. An HTML button beneath the banner works even when images don't.
ALT TEXT EXAMPLES
Weak: alt="banner"
Weak: alt="Northwind logo on green background"
Strong: alt="Webinar: Faster spot quotes, Thursday 14 Nov, 11am ET"
Strong: alt="New: live market rates in every Northwind quote"
What to Look for in an Email Banner Generator
Judge a generator by what reaches the inbox, not by its template gallery. Run these checks with a real campaign.
| Check | What good looks like |
|---|---|
| Brand control | Your exact colors, fonts and logo saved once, applied everywhere |
| Correct sizes | Presets for your email width, with a 2x save option |
| File weight | Built-in compression without visible artifacts |
| Text handling | Lets you keep copy short and readable on a phone |
| Alt text reminder | Prompts you for alt text, or exports it with the image |
| Dark mode preview | Shows how the banner looks on a dark background |
Then send a test to yourself. Check Gmail, Outlook and a phone, with images on and off. Ten minutes of testing beats a campaign that arrives broken.
Which Emails Should Carry a Banner
A banner tells the reader what kind of email this is before they read a word. That's useful in a newsletter and harmful in a personal note. Use this as a quick rule.
| Email type | Banner? | Why |
|---|---|---|
| Newsletter | Yes | Readers expect it, and it signals the brand at a glance |
| Event or webinar invitation | Yes | The banner carries the title and date |
| Customer announcement | Optional | Helpful for big changes, noise for small ones |
| Post-meeting recap to a prospect | No | It should read like a note from you |
| Cold or one-to-one sales email | No | It looks like a mass send and adds deliverability risk |
| Internal update | Rarely | Only for recurring digests people scan |
Signatures are a separate question. A small signature banner on replies to existing contacts is common. On first-touch cold email, many sellers use a plain text signature.
Email Banner Copy Templates
Write the banner as one headline and one line. Everything else belongs in the email body. Match the banner headline to your subject line, so the reader who opened for that promise sees it confirmed instantly.
Newsletter header
[Newsletter name]: [issue theme in 5 words or fewer]
[Month, year]
Product announcement
New: [capability in plain words]
[One-line benefit for the reader]
Event invitation
[Outcome-led title]
[Day, date], [time and timezone]. [Online or city].
Customer announcement
[Change that affects the customer], starting [date]
What it means for you, below
Banners vs Linked Visuals in Sales Email
In one-to-one sales email, swap the banner for a link. A designed header says "mass send" before the prospect reads a word, and an image that gets blocked or filtered costs you the conversation. If replies have dried up, our cold email not getting replies guide helps you diagnose whether deliverability is the cause.
Keep the visual, change where it lives. Put it on a page and link to it from a plain-text email. That's the core idea in our guide to the personalized image for cold email, and it's how a sales infographic earns its place in outreach. For banners outside email, see the sales banner guide.
Edithly builds that linked visual for each prospect. It creates an on-brand infographic for a specific account from their website and your product playbook, hosted on a share link with a view count, so your email stays plain and the visual stays rich.
How Edithly does it
Make an on-brand visual for one prospect in three steps
Edithly doesn't generate email banners. It builds an on-brand Infographic for a specific prospect, hosted as a link, which is the safer way to add a visual to sales email: link to it instead of embedding an image.
- 1
Click the Infographic tile
On Home, pick Infographic. Your logo, colors and fonts are already in your playbook, read from your website when you added the product.
- 2
Enter the prospect's details
Add the company name and website. In Notes, give the angle you want the visual to make, such as 'cost of slow spot quotes'.
- 3
Generate and link it
Click Generate infographic, pick a style, then copy the share link into a plain-text email. The view count shows whether it's been opened.
Website
Ready
- Their numbers
- The gap
- Your process
- Outcome
- Styles
- Copy link
- By hand
- 45 to 90 minutes per visual in a design tool
- With Edithly
- A couple of minutes per account
Frequently asked questions
What size should an email banner be?
Match your email's content width, which is commonly around 600 to 640 pixels. Save the image at twice that width for sharp display on high-resolution screens and set its display width in the HTML. Keep the height modest so live text shows in the preview pane, and keep the file as small as quality allows.
Do images in emails hurt deliverability?
Images alone don't send mail to spam, but they change how an email looks to filters and people. Image-heavy emails with little text resemble marketing mail, heavier messages load slower, and some clients block external images by default. For one-to-one sales email, plain text with a link is the lower-risk choice.
What is alt text in an email banner?
Alt text is the description in the image's HTML that displays when the image is blocked and is read aloud by screen readers. Write what the banner says, not what it looks like: 'Webinar: Faster spot quotes, 14 Nov, 11am ET' beats 'banner image'. Keep it short and include the key message.
Should I put a banner in my sales emails?
Not in cold or one-to-one sales emails. A designed banner signals a mass send and adds deliverability risk. Banners suit newsletters, event invitations and customer announcements. If you want a visual in a sales conversation, link to a page or infographic built for that prospect and keep the email itself plain.
Can Edithly create email banners?
No. Edithly doesn't generate email banners or header images. It builds on-brand visuals for a specific prospect, such as an Infographic or One Pager, from their website and your playbook. Each is shared as a link with a view count, so you can reference it from a plain-text email instead of embedding an image.