This article will show you how to encode a dynamic value into your barcode. This means each barcode can be unique to each pass issued. This is useful if you have your own value (like a membership number, SKU, POS code, or a unique URL).

There are 2 options.

Encode a value from a field already on the pass
Encode a value to be added when the pass is created (When using Zapier or the API)

Terminology

Barcode Payload

The data encoded within the barcode.

Dynamic Value

A value that changes or is unique for each barcode.

Field Key

A unique identifier for a specific data field within the pass.

Placeholder

A representation of a field key within the barcode payload, denoted by curly brackets (e.g., ${fieldkey}).

Meta Field

A custom data field that stores additional information, often used for dynamic barcode values.

API (Application Programming Interface)

A set of rules and specifications that software programs can follow to communicate with each other.

Zapier/Make

No-code automation platforms used to connect and integrate different applications.

Encode a value from a field already on the pass

You can encode the content of any field on the pass into the barcode.

To do this we need to add a placeholder in the barcode Payload field. This is made up by taking the field key and wrapping it in curly brackets.

Example - ${fieldkey}

The field key can be found in the field settings.

Finding the field key

Click on the field to open the field settings.

Using the example above, the placeholder will be ${meta.myData}

Adding the placeholder to the barcode Payload

This can then be added to the Encoded Barcode Content field.

Encode a value to be added when the pass is created (When using Zapier or the API)

With this option the data must be provided when the pass is issued. This can be done via the API or a no code solution like Zapier and Make.

In this case, you can provide any meta field key, making sure to populate this field when issuing the pass.

Example,

If I set the placeholder in the Barcode Payload field to be ${meta.barcode}, then I must use the following parameters when creating the pass using the API.

"metaData": {
        "barcode": "My Barcode Value"
}

This data isn't displayed anywhere else on the pass, but is stored in the pass record and is used to populate any field with the corresponding placeholder.

Encoding a Dynamic URL in the Barcode

In some cases, you may want to encode a unique URL per pass that links to your backend system.

This can be useful if your scanning environment:

Opens a browser automatically when a pass is scanned, or
Does not support direct lookup of an identifier via a POS or scanner integration

In many implementations, a better approach is for the scanner or POS system to read a unique identifier (such as a membership number or token) and perform a lookup directly. However, encoding a URL can be a practical alternative where that is not possible.

How it works

You store a value (typically a secure token or full URL) in a field, then reference that field in the barcode using a placeholder.

Option A – Build the URL in the barcode

Store a token in a meta field, for example:

meta.secureToken = abc123xyz

Then set the barcode payload to:

https://yourdomain.com/member/${meta.secureToken}

When the pass is issued, this becomes:

https://yourdomain.com/member/abc123xyz

Option B – Store the full URL in a field

Store the full URL in a meta field:

meta.dynamicUrl = https://yourdomain.com/member/abc123xyz

Then set the barcode payload to:

${meta.dynamicUrl}

Providing values via the API

If you are creating passes via the API, you can pass the value at the time of issuance:

"metaData": {
  "secureToken": "abc123xyz"
}

"metaData": {
  "dynamicUrl": "https://yourdomain.com/member/abc123xyz"
}

Best practice

Where possible, use the barcode to encode a unique identifier and perform lookups directly in your POS or backend systems.

If using URLs:

Use a short, secure token (not personal data)
Resolve all data server-side
Keep the URL length reasonably short for reliable scanning

Related: How much data can be stored in a barcode or QR code?

When encoding dynamic values (especially URLs), it’s important to keep the barcode payload at a reasonable length to ensure reliable scanning across devices and scanners.

Refer to this article for details: How much data can be stored in a barcode?

This article explains: