Understand and optimize INP: This is how your Shopware 5 or 6 shop will noticeably become faster and more successful

Finally, the product detail page has loaded and he can select the color of the leather; he chooses brown, and slowly the price and availability of the variant adjust before his eyes, but it slightly stalls. Hastily, he puts the smartphone in his pocket, as the elevator has reached the right floor and he steps out. The cool men's handbag he was just about to purchase will unfortunately be forgotten and he'll never return to the online shop. Our world has become fast, and if an online shop can't keep up, it loses sales.

Interacción hasta la siguiente pintura

Since March 2024, a new metric is on everyone's lips—particularly among shop operators, developers, and SEOs: INP, short for "Interaction to Next Paint." This metric is not only technically intriguing but also a reliable indicator of the perceived speed of an online shop. But why is Google suddenly so focused on interaction speed? What is behind the supposed technical jargon? And how can Shopware shops, in particular, avoid falling behind here?

INP is a decisive performance signal

As a specialized Shopware agency with more than 15 years of experience in development and SEO, we give you a deeper insight: We explain why INP is crucial for your shop, what you must definitely pay attention to when measuring, and how you can noticeably improve your customers' shopping experience through targeted optimizations.

Since spring 2024, INP is officially a Core Web Vital, and thus a direct ranking factor. In other words: if you don't have your Shopware instance under control, you lose twice - in visibility and with individual customers.

What is INP anyway? – A new benchmark for the "perceived" speed

Imagine you visit a webshop, click on a filter, want to add your favorite product "to the cart" or navigate through different categories. How fast does the page feel? Does it respond almost simultaneously, or do you let the mouse pointer circle around before something happens? This is exactly where INP comes in.

Unlike previous metrics such as FID ("First Input Delay"), which only captured the moment up to the first technical processing of a user action, INP evaluates the entire time span—from your click to the visible reaction of the website. The goal: To truly measure how "lively" your page feels to real people.

• What is being measured?
  Clicks, touch inputs, opening menus or filters - all typical interactions in the online shop.

• What is considered good?
  Google sets strict standards: Under 200 milliseconds is considered optimal. Up to 500 ms is still acceptable, beyond that it becomes critical for user experience and SEO.

Why is INP particularly important for Shopware operators?

In e-commerce, speed determines sales. This may sound clichéd, but it can be demonstrated with numerous studies: Even tiny delays of 100 to 200 milliseconds can measurably lead to purchase abandonments—especially among mobile users. In an online shop, interaction follows interaction: Products are filtered, variants selected, added to the shopping cart, or purchased via one-page checkout. Every delay adds up, every disruptive second results in declining conversion rates and—since Google's INP introduction—also affects search engine rankings.

How does one measure INP meaningfully? – From laboratory values and real user experiences

For many technical metrics regarding web performance, there are two different measurement methods:

• Laboratory data:

  Here, websites are automatically tested "in a test tube" – for example, with tools like Google Lighthouse or WebPageTest. They provide quickly reproducible results and help test code changes in detail. However, they never fully depict reality, as no real user behavior, varying internet speeds, or mix of devices are taken into account.

• Real User Monitoring (RUM):

  This measurement is based on data from real visitors to your shop, meaning actual interactions and real everyday devices. Tools like PageSpeed Insights (with CrUX report), Google Search Console, or browser extensions show you how your pages perform "in the wild." These values are crucial for Google.

And how does the Top 100 measureSEOAgency? – Tip from practice

For a complete picture, you should use both methods: lab data helps with troubleshooting and development, while RUM data shows how your measures are received by real customers. If that's not enough, you can turn to professional tools like Tideways (specialized in PHP backends like Shopware) or New Relic (comprehensive APM solution). These allow you to identify and specifically optimize bottlenecks both in the backend (e.g., slow database queries) and in the frontend (slow scripts, computationally intensive JavaScript components).

Typical INP Brakes in Shopware 5 and 6

Depending on the Shopware version, there are specific vulnerabilities that repeatedly appear as the cause of high INP values:

Shopware 5

• Older, jQuery-laden architecture with many DOM manipulations

• Plugins that block or overwrite global event handlers

• Little native support for lazy loading and modern JavaScript conventions

• Modal popups (newsletter, promotions), complex filters that lead to long processing times

Shopware 6

• Modern Vue-based frontend architecture: Advantages in performance, but risky for very dynamic or overloaded CMS pages

• Complex components such as sliders, filter overlays, which increase rendering time

• Injected third-party scripts (e.g., tracking, marketing tools) can slow down event handling – without it being immediately visible

© StockWorld – stock.adobe.com

What can be done against poor INP values? – Concrete measures

The good news: Almost always there are levers you can turn without a complete overhaul.

For all Shopware versions, the following applies:

• Revise your JavaScript bundles: Can certain scripts be outsourced, split, or even removed?

• Use "passive" event listeners when responding to scroll or touch movements (this relieves the main thread of your browser)

• Reduce DOM changes – for example, by bundling all filter actions instead of processing them individually

• Load third-party scripts (such as for tracking or chat widgets) asynchronously afterwards

• Remove or "lazy load" non-essential UI components

Specific to Shopware 5:

• Check which jQuery plugins are really needed and throw out the ballast.

• Use caching strategically in Ajax requests, such as when loading filter results.

• Keep theme-specific JavaScript lean and avoid functions for checkout/cart on irrelevant pages

Specific to Shopware 6:

• Disable unused or rarely used CMS elements (e.g., tabs or overlays)

• Avoid CMS blocks with a high JavaScript content – or outsource them if desired

• Regularly test and optimize Vue components, especially where they are heavily used interactively.

• Actively monitor the third-party plugins – both technically and content-wise

© rh2010 – stock.adobe.com

Interaction speed – Your key to more success in the shop

With INP, Google is once again focusing on the actual user experience. Today, technical optimization means much more than just offering fast loading times—what is needed is a holistic view of the entire interaction chain. Because: INP is much more than just a technical gimmick. Interaction to Next Paint shows you how smooth your shop feels to real customers—and has been directly contributing to Google rankings and thus to your business success since 2024.

Successful Shopware shops focus on the interplay of Core Web Vitals, targeted CSS tuning, optimized JavaScript performance, and thoughtful UX design. Only in this way can shops convincingly impress both users and search engines in the long term.

Don't wait for the next relaunch!

Regularly check your INP values, rely on the combination of real user data and laboratory analyses – and invest specifically in measures that improve not only metrics but above all the shopping experience of your visitors.

We are happy to support you as an experienced Shopware agency: We analyze your shop, identify performance brakes, and implement realistic, measurable improvements with you – so that quick reactions turn into sustainable business success.