What does the WooCommerce plugin do?

Two things. First, it installs the Otter SDK in your site's with anti-flicker — exactly like pasting the snippet by hand, but managed for you. Second, it tracks your commerce funnel automatically: product views (ViewContent), searches (Search), add-to-cart (AddToCart), checkout starts (InitiateCheckout), and completed orders (Purchase) with their revenue. It brings WooCommerce up to the same automatic tracking you get from the native Shopify integration.

Download the plugin zip from your project's installation page (the Download the WooCommerce plugin button under the WooCommerce guide). In WordPress admin, go to Plugins → Add New → Upload Plugin, choose the zip, click Install Now, then Activate. Open Settings → Otter A/B Testing, paste your project API key, and save. That's the whole setup — no theme files to edit.

Where do I find my API key?

In your Otter dashboard, open the project and go to the installation page. The 22-character key is shown there (and is pre-filled in the plugin's install steps). Paste it into Settings → Otter A/B Testing in WordPress.

How is revenue attributed to a variant?

When a visitor lands on your store the SDK assigns them to a variant and stores a first-party optimo_uuid cookie. Because the WooCommerce thank-you page is on your own domain, that cookie is available there. On the order-received page the plugin fires a Purchase event carrying the order total, currency, and id, and Otter credits that revenue to the visitor's assigned variant. The order data comes straight from WooCommerce (PHP), not from scraping the page, so it's exact.

Will a purchase be counted twice if the customer refreshes the thank-you page?

No. Each Purchase event includes the order id, which Otter uses as a deduplication key. Refreshing the confirmation page, bookmarking it, or coming back later won't double-count the sale.

Does it work with High-Performance Order Storage (HPOS)?

Yes. The plugin uses the WooCommerce CRUD API for all order access and declares HPOS compatibility, so it works whether your store uses the classic post-based order storage or the newer high-performance order tables.

Do I still need to paste the snippet or use a header plugin?

No. The plugin injects the SDK loader for you, so you don't need WPCode or any header/footer plugin alongside it. If you were previously using a manual snippet, remove it after activating the plugin to avoid loading the SDK twice.

Can I turn off commerce event tracking or customer email?

Yes. Settings → Otter A/B Testing has toggles for anti-flicker, commerce-event tracking, and sending the customer email on purchase (used to identify visitors across devices). The email toggle is on by default and mirrors the Shopify integration; turn it off if you'd rather not pass the buyer's email.

What if I can't install a plugin — is there a manual option?

Yes. The WooCommerce installation page has an advanced Prefer a manual install? section with the head snippet plus example helper code for firing AddToCart and Purchase events from your theme. The manual route is more fragile and you maintain it yourself, so the plugin is the recommended path.

Does the plugin require WooCommerce, or does it work on any WordPress site?

The SDK loads on any WordPress site, so you can run A/B tests even without WooCommerce. The commerce events (product view, add-to-cart, checkout, purchase) activate automatically when WooCommerce is active. On a non-Woo WordPress site the plugin simply loads the SDK and the settings page notes that commerce tracking is idle.

Getting Started5 min read

WooCommerce Plugin

Install the official plugin to load the SDK and auto-track the WooCommerce commerce funnel, including revenue.

Browse docs

Install the official Otter plugin to load the SDK and automatically track your WooCommerce commerce funnel — including purchases with revenue — without touching your theme.

Whole-theme split tests

The same plugin works on WordPress without WooCommerce and can split visitors between complete installed themes. In Settings → Otter A/B Testing, approve the themes Otter may serve, confirm cache safety, choose an approved theme, and click Create a WordPress theme split test. Otter opens a prefilled site-wide wizard with the current theme as control.

The plugin selects the assigned theme for each request; it never invokes WordPress's global Switch theme action. For opt-in projects, no assignment is stored or applied until consent is explicitly granted.

Cache requirement: Exclude the otter_theme_assignment cookie from full-page cache at every cache/CDN layer, or use no full-page cache while the test runs. Theme setup stays disabled until an administrator confirms this boundary. Object caching is compatible.

Shopify gives opt-out projects a native pixel that reports completed orders with structured data; opt-in projects keep it disconnected because Shopify's pixel sandbox cannot inherit the theme consent decision. The WooCommerce plugin brings WooCommerce to the same level: it injects the Otter SDK in your site's <head> with anti-flicker, and tracks product views, searches, add-to-cart, checkout starts, and purchases for you. Order data (total, currency, line items) comes straight from WooCommerce in PHP — not scraped from the page — so your revenue numbers are exact.

Because the WooCommerce thank-you page is on your own domain, the visitor's first-party optimo_uuid cookie is available there, so each purchase is attributed to the variant that visitor saw. Revenue is deduplicated by order id, so a refreshed confirmation page never double-counts a sale.

1
Download the plugin
On your project's installation page, open the WooCommerce guide and click Download the WooCommerce plugin.
2
Upload and activate
In WordPress admin go to Plugins → Add New → Upload Plugin, choose the zip, click Install Now, then Activate.
3
Paste your API key
Open Settings → Otter A/B Testing, paste your project API key, and save. The SDK starts loading immediately.
4
Verify
Place a test order if you can, then click Verify Installation on your Otter project page. You should see commerce events arrive.

Events tracked automatically

ViewContentProduct page viewed

SearchSearch submitted

AddToCartProduct added to cart

InitiateCheckoutCheckout started

PurchaseOrder completed (with revenue)

Configure a goal against any of these event names to score it. To score revenue, add a Revenue goal with the event name Purchase — see the Goals and Revenue & Currency guides.

Under the hood, the plugin calls the SDK with the order data on the thank-you page — equivalent to:

optimo.revenue({
  value: 129.0,
  currency: 'USD',
  order_id: '1042',
  quantity: 2,
})

WordPress plugin tips

Remove any old snippet. The plugin injects the SDK for you. If you were loading Otter via a header plugin or theme edit, delete that so the SDK isn't loaded twice.

It works without WooCommerce too. The SDK loads on any WordPress site for A/B testing; the commerce events switch on automatically when WooCommerce is active.

Toggles live in settings. Anti-flicker, commerce events, and sending the customer email on purchase can each be turned off under Settings → Otter A/B Testing.

Frequently asked questions

Quick answers to the questions teams ask most about this part of Otter.