Reducing push notification payload size

If you can’t launch a push campaign or Canvas step because your push payload is too large, check out these tips for reducing your push notification payload size.

What is a push payload?

Push service providers calculate whether your push notification can be displayed to a user by looking at the byte size of the entire push payload. The payload is limited to 4KB (4,096 bytes) for most push services, including:

• Apple Push Notification service (APNs)
• Android’s Firebase Cloud Messaging (FCM)
• Web push
• Huawei push

These push services will refuse any notification that exceeds this limit.

Braze reserves a portion of the push payload for integration and analytics purposes. Given that, our maximum payload size is 3,807 bytes. If your push exceeds this size, the message may not be sent. As a best practice, keep your payload to a few hundred bytes.

The following elements in your push make up your push payload:

• Copy, such as the title and message body
• Final render of any Liquid personalization
• URLs for images (but not the size of the image itself)
• URLs for click targets
• Button names
• Key-value pairs

Tips to reduce payload size

To reduce payload size:

• Keep your message brief. A good general guideline is to make it actionable and beneficial in less than 40 characters.
• Omit whitespace and line breaks from your copy.
• Consider how Liquid will render on send. Because the final render of any Liquid personalization will vary from user to user, Braze can’t determine if a push payload will exceed the size limit when Liquid is included. If your Liquid renders a shorter message, you might be fine. However, if your Liquid results in a longer message, your push may exceed the payload size limit. Always test your push message on a real device before sending it to users.
• Consider shortening URLs using a URL shortener.