Upgrade legacy promotional messsaging


Upgrading your Affirm integration allows you to take advantage of our upcoming and future releases as soon as they’re available with little or no development work. Our lightweight upgrade includes:

  • New promotional messaging components that respond dynamically to your unique financing programs such as longer terms (18, 24 and 36-month repayment terms) and 0% APR promotions, with customizable messaging to personalize the consumer journey
  • Our Prequalification flow within promotional messaging components to unlock purchasing power upfunnel while minimizing additional development work for your teams
  • Our updated Affirm.js library, which includes Enhanced Analytics that provide consumer insights and enable A/B testing to keep your site optimized

Recommended: Sandbox development

Perform this upgrade in your development environment connected to our sandbox. To connect your development environment to our sandbox, do the following:

  1. Add Affirm.js to the global page template

<!-- Affirm -->
	_affirm_config = {
		public_api_key: "{YOUR_PUBLIC_API_KEY}",
		script: "https://cdn1.affirm.com/js/v2/affirm.js",
		locale: "en_US",
		country_code: "USA",

(function(m,g,n,d,a,e,h,c){var b=m[n]||{},k=document.createElement(e),p=document.getElementsByTagName(e)[0],l=function(a,b,c){return function(){a[b]._.push([c,arguments])}};b[d]=l(b,d,"set");var f=b[d];b[a]={};b[a]._=[];f._=[];b._=[];b[a][h]=l(b,a,h);b[c]=function(){b._.push([h,arguments])};a=0;for(c="set add save post open empty reset on off trigger ready setProduct".split(" ");a<c.length;a++)f[c[a]]=l(b,d,c[a]);a=0;for(c=["get","token","url","items"];a<c.length;a++)f[c[a]]=function(){};k.async=
  !0;k.src=g[e];p.parentNode.insertBefore(k,p);delete g[e];f(g);m[n]=b})(window,_affirm_config,"affirm","checkout","ui","script","ready","jsReady");
<!-- End Affirm -->


The locale parameter allows Affirm to identify which locale you are serving your site in for any particular user. For example, let's say that you're rendering your site in Canadian French; perhaps this occurred because the user's browser setting detected Canadian French. You can provide Affirm with the user's language setting by passing it in the locale parameter. Affirm will then read the locale and translate the pages accordingly, thus, matching the language the user had seen on your site. However, we will not attempt to read the user's locale directly.


The country_code parameter represents the country of legal incorporation of your store, which is shown to any given user. So, if you're showing your American website/store to a user and you have a legal presence in the United States, you would pass USA into the country_code parameter. This allows us to determine which regulations to abide by and which banks to partner with for this transaction.

Supported values for locale and country_code

Affirm supports the following combinations for locale and country_code:

locale:en_US- (Language= Englishen- Country= United States US- for a locale that reads en_US)
locale:en_CA- (Language= Englishen- Country= Canada CA- for a locale that reads en_CA)
locale:fr_CA- (Language= Frenchfr- Country= Canada CA- for a locale that reads fr_CA)

The following will occur when a locale and/or country_code is not provided:

  • When a locale is not provided, the locale will default to en_US (English speaking US).
  • When a country_code is not provided, the country_code will default to USA.


  • Be sure to use your public API key from the sandbox merchant dashboard for public_api_key.
  • Your global page template is the only place where you need this embed code.
  1. Delete existing JavaScript from each page

Delete all instances of the JavaScript embed code you currently have from each page on your site. These pages include but may not be limited to the category, product, cart, and payment pages.

Search your page source for get_estimate to find the existing JavaScript embed code:

  (function(l,g,m,e,a,f,b){var d,c=l[m]||{},h=document.createElement(f),n=document.getElementsByTagName(f)[0],k=function(a,b,c){return function(){a[b]._.push([c,arguments])}};c[e]=k(c,e,"set");d=c[e];c[a]={};c[a]._=[];d._=[];c[a][b]=k(c,a,b);a=0;for(b="set add save post open empty reset on off trigger ready setProduct".split(" ");a<b.length;a++)d[b[a]]=k(c,e,b[a]);a=0;for(b=["get","token","url","items"];a<b.length;a++)d[b[a]]=function(){};h.async=!0;h.src=g[f];n.parentNode.insertBefore(h,n);delete g[f];d(g);l[m]=c})(window,_affirm_config,"affirm","checkout","ui","script","ready");
      affirm.ui.ready( function() { updateAffirmAsLowAs( 50000 ) } ); // change to your template value for product or cart price
  function updateAffirmAsLowAs( amount ){
    if ( ( amount == null ) || ( amount < 1000 ) ) { return; } // Only display as low as for items over $10 CHANGE FOR A DIFFERENT LIMIT
    // payment estimate options
    var options = {
      apr: "0.10", // percentage assumed APR for loan
      months: 12, // can be 3, 6, or 12
      amount: amount // USD cents
    try {
      typeof affirm.ui.payments.get_estimate; /* try and access the function */
    catch (e) {
      return; /* stops this function from going any further - affirm functions are not loaded and will throw an error */
    // use the payment estimate response
    function handleEstimateResponse (payment_estimate) {
      // the payment comes back in USD cents
      var dollars = ( ( payment_estimate.payment + 99 ) / 100 ) | 0; // get dollars, round up, and convert to int
      // Set affirm payment text
      var a = document.getElementById('learn-more');
      var iText = ('innerText' in a)? 'innerText' : 'textContent';
      a[iText] = "Starting at $" + dollars + " a month. Learn More";
      // open the customized Affirm learn more modal
      a.onclick = payment_estimate.open_modal;
      a.style.visibility = "visible";
    // request a payment estimate
    affirm.ui.payments.get_estimate(options, handleEstimateResponse);
  1. Add Affirm promotional messaging

Add an HTML element everywhere you want to display an Affirm promotional messaging component. The HTML element attributes determine which component displays. We generally recommend adding promotional messaging to your category, product, cart, and payment pages.

In each HTML element, include the new data-page-type attribute corresponding to the page where that promotional messaging component is placed. The data-page-type attribute allows you to customize messaging in the future without development work. See our HTML Reference for required attributes.

By default, promotional messaging on product pages have prequalification enabled, but you can work with your Client Success Manager to change this and configure additional customizations.

Monthly payment messaging (affirm-as-low-as) usually display price-specific information (requires data-amount) and are typically used with the following data-page-types:

  • category
  • product
  • cart
  • payment

Since site modals (affirm-site-modal) do not display price-specific information, they are typically used with the following data-page-types:

  • homepage
  • banner
  • landing
  • search

If you don't pass data-page-type, the component will use a default setting.


<p class="affirm-as-low-as" data-page-type="category" data-amount="99900"></p>

<p class="affirm-as-low-as" data-page-type="product" data-amount="99900"></p>

<p class="affirm-as-low-as" data-page-type="cart" data-amount="99900"></p>

  1. Add the Confirmation Page function

When a customer completes their purchase, you can send their order and product information to Affirm for A/B testing, which will help you optimize your site. Send this information by adding the Confirmation Page function to your payment confirmation page. We only require orderId, total, productId, and quantity for A/B testing.

  1. Test and set live

Confirm that all of your Affirm promotional messaging components display as expected.

After testing everything, update the script parameter in the Affirm.js embed code to point to our live environment at <https://cdn1.affirm.com> and replace the public_api_key parameter with your live public API key found at https://affirm.com/dashboard/#/apikeys.

After you've connected to our live environment, you're ready to deploy to your production environment.