Installation
Does Metrunio slow down my shop?
The tracking script loads asynchronously, alongside your page, and does not hold up its rendering. About 10.4 KB are transferred with Brotli or 11.6 KB with gzip, after which it sits in the browser cache. The consent bridge, another 10 KB or so, loads only if you connected a consent tool through it, and before the decision in the cookie banner the script sends nothing.
How much does the tracking script slow down my page?
| File | Uncompressed | Transferred (Brotli / gzip) | When it loads |
|---|---|---|---|
| Tracking script (t.js) | 34.4 KB | 10.4 KB / 11.6 KB | on every page |
| Consent bridge (consent-bridge.js) | 31.4 KB | 9.5 KB / 10.6 KB | only if you chose a consent bridge in the embed code |
Measured on 17.10.2026 on the built files, compressed the way Metrunio serves them. Modern browsers get the Brotli version, older ones gzip.
What “asynchronous” means here
The embed code adds the script with the async attribute. The browser loads it on the side while it renders text, images and the cart, and waits for Metrunio with none of it. What the script measures it sends in batches in the background. If the measurement address is unreachable for a moment, your customer notices nothing: the events wait in the browser and go out later.
After the first load the browser keeps the script for an hour and then fetches the new version in the background, while it goes on using the old one for up to a day. On the second page of a visit, as a rule, nothing is transferred any more.
With the Shopify app
The app embed loads the same script asynchronously and the consent bridge not at all: the app reads consent through Shopify. In checkout, the pixel the app creates on connecting measures inside the sandbox Shopify provides for pixels, and Shopify reports the order itself to Metrunio without anything happening in the browser.
Note
An automated test keeps the tracking script at no more than 12 KB with gzip; if it grows beyond that, the test fails. We have not measured a before-and-after value in PageSpeed Insights. If you want to know for your shop, measure the home page there once with and once without Metrunio.
Last reviewed on 17 Oct 2026
Also asked
- Does Metrunio slow down my shop?
- Will tracking make my website slower?
- How large is the tracking script?
- Does Metrunio affect PageSpeed?
- Does the script hurt Core Web Vitals?
- Does the script load asynchronously?
Related articles
- How do I install the code snippet?
How do I install Metrunio without a tag manager?
The finished code block is in the portal under “Setup → Snippet” and contains site ID and collector address. You see the write key only once, when it is created; if it is no longer known, the code carries the placeholder YOUR_WRITE_KEY and a button next to it creates a new one. The block belongs immediately before the closing head tag and loads asynchronously.
- How do I set up Metrunio in Shopify?
How do I connect my Shopify store to Metrunio?
You install the Metrunio app in your store via its installation link: from the setup assistant in the portal or from our email. If you do not have a Metrunio account yet, the app creates one without a second sign-up once you accept the terms and conclude the data processing agreement with two tick boxes; an existing account you connect by signing in to the portal. Measurement starts only once the DPA is concluded, and then covers storefront, checkout and order at once, with no change to your theme code.
- How does Metrunio take the decision from my consent tool?
Do I have to call metrunio.setConsent myself if I use Usercentrics, Cookiebot, Complianz, Borlabs Cookie, Real Cookie Banner or another common consent tool?
Through the consent bridge, without you calling
metrunio.setConsentyourself: for thirteen tools this small additional script reads the decision from your banner and passes it to Metrunio, including every later withdrawal. The installation code in the portal contains it as soon as you choose your tool in the consent step, and the Shopware plugin adds it by itself. - What does the tracking SDK offer?
Which JavaScript calls are available?
The SDK provides init, setConsent, page, track, identify, conversion, goal and reset, plus paymentReference for Stripe and PayPal, fillForm for forms, and renderSurvey and survey for the post-purchase question. It loads asynchronously, queues calls made before it loads, and sends events in batches.
- What happens without consent?
Is nothing really stored without consent?
By default, Metrunio stores nothing without matching consent, not even a raw event, and the tracking script sends nothing before a decision. One documented case differs: purchases and refunds your server reports without consent count towards measured revenue for revenue reconciliation, with their order number and without browser, customer or advertising identifiers, and are not attributed. After a refusal this only applies with an activated additional instruction. Without consent on the ad side, the click redirect passes on only the campaign, no click ID.