Create Gmail ads with custom HTML

Gmail ads campaigns are now “read only”, which means that advertisers will not be able to create new Gmail campaigns or make changes to existing campaigns. This includes edits to any existing Gmail ads.

To continue serving ads on Gmail, we recommend that you create a Discovery campaign. Discovery ads allow you to expand your reach from Gmail to other Google-owned surfaces, which reach 3 billion people monthly and include YouTube and Discover. Learn more about creating and managing Discovery ads

Suitable for advanced advertisers, custom HTML lets you create ads different from existing Gmail ad templates. These ads can include video and multiple calls-to-action. To create Gmail ads with your own customized layout, upload your own custom HTML files into Google Ads.

This article explains how to configure and upload your custom Gmail ads.

Before you begin

Important: Keep in mind that custom HTML Gmail ads retain a destination URL formatting, and are incompatible with final URLs and tracking templates. Learn more about Upgraded URLs.


A custom HTML Gmail ad is a ZIP folder that contains all the files for your collapsed and expanded ad. To avoid problems, pay close attention to the strict formatting specifications detailed below.

The overall size limits of your ad are the following:

  • Your total ZIP folder: <1.25 MB
  • Number of files: <100 files
  • File size: <500KB

How to create your collapsed ad

For your collapsed ad, you’ll add 2 files to your ZIP folder:

  • the logo image (named “logo.png,” “logo.jpg,” or “logo.gif”)
  • the text file (named “‘teaser.txt”)

Logo image specifications

The file must be named exactly “logo.png,” “logo.jpg,” or “logo.gif” and the file format must be PNG, JPG, or GIF.

  • Logo image size: maximum 144px x 144px with aspect ratio 1:1
  • Maximum file size: 150KB
  • File formats: PNG, JPG, or GIF (non-animated)

The logo image is a small icon, graphic or brand logo.

The image will be displayed as a 50 x 50 square on normal resolution devices, but we accept up to 150KB for clearer viewing on some screens.

Text file specifications

The file must be named exactly “teaser.txt”  and the file format must be TXT. Here’s an example of a properly formatted text file.

Advertiser: Business Name
Subject: Everything 20% Off at Business Name
Description: Buy new products at low prices!
Display Url:
Landing Page:

Note: Follow the example exactly and be sure to enter the headings in English exactly as shown below. Also, be sure to include both the category (like “Advertiser”) and your specific information. The table below gives character limits and more guidance about what to include.

Headings Character limits What to include
Advertiser 20 Your company’s name or domain.
Subject 25 Your title can include an offer, % discount, or compelling announcement.
Description 90 Your description can be a short summary or a call to action.
Display URL 32 Your URL, as it will show in your ad
Landing page no limit Teaser redirect URL --used as the destination url for clicks on the "Sender displayed short URL" when the Expanded Ad is opened. You can add a static click tracking URL in this field. This is the page people will land on after clicking your display URL.


How to create your expanded ad

For your expanded ad, you’ll add 1 HTML file and 1 image folder to your ZIP folder:

  • Image Folder (named ‘Images’) containing image files for the expanded ad
  • HTML file named exactly “‘index.html”

Image folder specifications

  • Your ad must contain at least 1 image, and can contain up to 100 images. To embed videos in your expanded ad, jump to the video section below.
  • Max width per image: 650px
  • Max height per image: 1000px (Note: For the most effective ads, we recommend of no more than 650px height for the total ad canvas, which includes all your text and images.)

HTML file specifications

Technical Details

  • URLs: Must contain at least 1 absolute URL (can contain up to 15) and all special characters must be encoded (e.g. spaces, #).
  • Formatting: Control the layout using standard HTML tables to ensure consistent presentation across devices
  • Tracking: Static tracking URLs can be used to track external clicks. Impression tracking pixels and dynamic tracking URLs are not permitted. If you are using the "Gmail custom HTML ad" template, make sure to add the tracking URLs you want to use in the index.html file as well as in the teaser.txt file.
  • Markup: HTML (use UTF8 encoding), some HTML5 tags ( "ARTICLE", "ASIDE", "FIGCAPTION", "FIGURE", "FOOTER", "HEADER", "MARK", "SECTION", "TIME", "WBR"), and some CSS (style attribute of tags only e.g. <div style="color: black" >) are supported

Markup not permitted

  • Javascript: <script> tags will automatically be removed from the ad
  • Stylesheets: <link> tags will automatically be removed from the ad
  • Flash
  • HTML5: The only supported tags are "ARTICLE", "ASIDE", "FIGCAPTION", "FIGURE", "FOOTER", "HEADER", "MARK", "SECTION", "TIME", "WBR"
  • Audio
  • iFrames
  • Animated images: GIFs

Supported CSS

azimuth border-right-color font-size-adjust list-style padding-bottom text-decoration-style
background border-right-style font-stretch list-style-image padding-left text-emphasis
background-attachment border-right-width font-style list-style-position padding-right text-emphasis-color
background-blend-mode border-spacing font-synthesis list-style-type padding-top text-emphasis-style
background-clip border-style font-variant margin pause text-indent
background-color border-top font-variant-alternatives margin-bottom pause-after text-justify
background-image border-top-color font-variant-caps margin-left pause-before text-kashida-space
background-origin border-top-left-radius font-variant-east-asian margin-right pitch text-orientation
background-position border-top-right-radius font-variant-ligatures margin-top pitch-range text-overflow
background-repeat border-top-style font-variant-numeric marker-offset quotes text-transform
background-size border-top-width font-weight max-height richness text-underline-position
border border-width height max-width speak unicode-bidi
border-bottom box-sizing image-orientation min-height speak-header vertical-align
border-bottom-color caption-side image-resolution min-width speak-numeral voice-family
border-bottom-left-radius clear ime-mode mix-blend-mode speak-punctuation white-space
border-bottom-right-radius color isolation object-fit speech-rate width
border-bottom-style direction layout-flow object-position stress word-break
border-bottom-width display layout-grid opacity table-layout word-spacing
border-collapse elevation layout-grid-char outline text-align word-wrap
border-color empty-cells layout-grid-char-spacing outline-color text-align-last writing-mode
border-left float layout-grid-line outline-style text-autospace zoom
border-left-color font layout-grid-mode outline-width text-combine-upright  
border-left-style font-family layout-grid-type overflow text-decoration  
border-left-width font-feature-settings letter-spacing overflow-x text-decoration-color  
border-radius font-kerning line-break overflow-y text-decoration-line  
border-right font-size line-height padding text-decoration-skip  

Add a video to your expanded ad HTML file

  1. How to add a video

    A YouTube video can be embedded into an ad with a preview window. When someone using a computer clicks the video image, the video will play in a lightbox within Gmail. After the user is done watching the video, they are returned to the Gmail expanded ad. On mobile, the video will play on the person’s designated video player (like the YouTube app or a browser).

    Instructions: To add video from YouTube, code the YouTube link, image source, and display text to be appropriate for your ad. For example:

    <a href=""><img src="images/play.jpg" alt="Gmail Video"></a>

    Note: When you preview the ad in Google Ads, the YouTube video will not show or play in the lightbox.

  2. How to add a video in new tab

    If you want the video to play in YouTube in a new tab, rather than in a lightbox, set the class as "nonplayable.”

    For example:

    <a href="" class="nonplayable"><img src="images/play.jpg" alt="Gmail Video"></a>

  3. Important: include a “play” button in your preview image.

    To show people that clicking the image will play a video, your preview image should include some type of play button. Google Ads does not add anything to preview images to indicate that they are videos.

Related links

Was this helpful?
How can we improve it?

Need more help?

Sign in for additional support options to quickly solve your issue

Clear search
Close search
Google apps
Main menu
Search Help Center