Understanding VWO SmartCode: The Engine Behind Better Optimization Campaigns

6 Min Read
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Understanding VWO SmartCode: The Engine Behind Better Optimization Campaigns

6 Min Read
Request Demo Start Free Trial
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Over 2500 companies use VWO daily, running optimization campaigns to improve their KPIs and create better user experiences.

Behind every campaign, there is a technology that works quietly in the background, making everything possible. It is VWO SmartCode.

VWO SmartCode is a single piece of code that connects your website to VWO’s complete capabilities, encompassing everything from behavioral analytics to personalization. The code snippet contains your unique Account ID and allows your website to interact with VWO servers. 

But what makes VWO SmartCode special? Let’s find out in this blog.

Feature Image Understanding Vwo Smartcode The Engine Behind Better Optimization Campaigns

Key benefits that make VWO SmartCode special

VWO SmartCode delivers several advantages that make your optimization campaign both seamless and accurate. Here’s what sets it apart. 

1. Flexible loading options for every website type 

VWO SmartCode offers the flexibility to match your website’s specific needs through two loading approaches.

Asynchronous loading: When visitors land on your site, your webpage loads at normal speed while VWO quietly runs in the background. If everything connects properly, your optimization campaigns, such as A/B tests or personalized experiences, will start running. If there’s a slow connection or server issue, visitors see your original page without any problems. 

Its benefit is that the website never slows down, and visitors don’t see broken pages.

Best for: Most websites, e-commerce stores, and blogs where site speed is the top priority.

Synchronous loading: Sometimes you need precise control when things load. That’s where synchronous loading helps. This version loads VWO in a single, clean request and caches the response for faster repeat visits.

VWO Async and Sync SmartCode
VWO Asynchronous and Synchronous SmartCode

2. Minimal impact on core web vitals 

VWO SmartCode is built for performance, keeping your website fast while running an optimization campaign. It has a minimal impact on core web vitals like First Contentful Paint (FCP), Largest Contentful Paint (LCP), Cumulative Layout Shift (CLS), and Interaction to Next Paint (INP), through smart technical design.

a. Efficient client-side execution via web workers 

VWO offloads heavy computations and client-side event tracking to web workers, allowing these operations to run in a background thread without blocking the main thread. This allows your website’s UI rendering and user interactions to remain smooth and responsive during complex optimization campaigns. By isolating logic like variation rendering, tracking, and targeting calculations, web workers help maintain a seamless experience for your visitors.

b. High-speed delivery with geo-distributed load balancers 

VWO uses global load balancers and geo-distributed servers powered by Google Cloud CDN to reduce latency and ensure fast content delivery. Google Cloud CDN utilizes a global network of points of presence (PoPs) to deliver content to visitors. It has strategic locations across the globe and automatically serves resources from the data center closest to your user. This minimizes load times and reduces strain on your origin server. Whether your visitors are in North America, Europe, South America, or Asia-Pacific, they receive VWO assets with minimal delay.

Global Network Of Points Of Presence (pops)
VWO global network with points of presence (PoPs)

Unlike standard CDNs that only cache static files, VWO’s dynamic CDN caches both static code and generates dynamic test variation data in real-time. 

Additionally, the system generates tailored campaign settings based on specific URLs, device, locations, traffic source, and other relevant parameters. This helps deliver only relevant variation data and eliminates unnecessary information. Its infrastructure advantage leads to faster loading times and better user experiences across all your campaigns.

Vwo Content Deliver Network
Campaign delivery mechanism

The result? You can run sophisticated optimization campaigns without performance penalties. Visitors stay engaged with fast, responsive experiences, and search engines reward your site with better rankings.

3. Built-in performance monitoring for complete transparency and visibility

VWO SmartCode proves its minimal performance impact through built-in monitoring tools rather than just promising it. The Performance tab displays real impact data on your core web vitals after SmartCode installation, using Google PageSpeed Insights (PSI) in the background to analyze page performance with complete transparency.

You can track FCP, LCP, and Thread Blocking Time (TBT) metrics separately for both mobile and desktop devices.  The system performs comparisons with and without VWO to calculate the exact impact on these metrics, giving you precise visibility into how campaigns affect your site performance. The detailed breakdown shows VWO library sizes and individual campaign impacts by type, with the total size of all campaigns displayed at the bottom. This transparency lets you monitor performance impact and make informed decisions about your optimization strategy.

Vwo Smartcode Performance Report
VWO SmartCode performance report

4. Flicker-free loading protects your brand image

Page flicker ruins user experience and makes websites look unprofessional. VWO Asynchronous Code prevents page flicker by hiding page elements before they load, then revealing them only after VWO campaign variation changes are properly applied.

This anti-flicker protection works automatically by default. Your visitors never see content jumping around or styling issues during page loads.

Most optimization tools slow down page rendering with blocking code. VWO’s approach ensures your site always looks polished and professional, maintaining the quality experience your brand deserves.

5. Integration for seamless SmartCode deployment

VWO SmartCode integrates seamlessly with most major content management systems and website platforms, making implementation straightforward regardless of your technical setup.

With 40+ integrations, you can deploy SmartCode across popular platforms including Shopify, WordPress, BigCommerce, Drupal, Joomla, Wix, Magento, Squarespace, HubSpot, and many more. These integrations ensure SmartCode loads properly on every platform while maintaining optimal performance.

The above benefits associated with VWO SmartCode showcase how businesses can rely on it for their modern optimization programs. 

Adding VWO SmartCode to your website

Now let’s walk through the simple process of implementing VWO SmartCode on your digital platforms. Implementation is straightforward with two available methods depending on your technical setup.

1. Automatic installation

Deploying SmartCode is straightforward with your existing platform. Simply install the VWO plugin or app on your platform, or connect directly through the integrations section in your VWO dashboard, and you’re ready to start optimizing. VWO currently supports 40+ popular platforms. You can check out all the platforms on the integrations page.

2. Manual installation

Copy the SmartCode directly from your VWO dashboard after registering your website. Paste the code into your website’s head tags, and VWO begins tracking immediately. This method works for any website or digital product regardless of the platform.

Both approaches get you up and running quickly, so you can focus on creating optimization campaigns.

Ready to experience VWO in action?

Whether you’re running a simple blog or a complex Single Page Application, we’ll demonstrate how VWO SmartCode maintains your site’s performance while delivering reliable data.

Book your personalized demo today and discover why over 2500+ companies trust VWO for their optimization needs.

Ketan Pande
I’m a content marketer at VWO, reading and writing on topics like behavior analytics, conversion rate optimization, and experimentation. Prior to VWO, I built and managed my own website where I discussed business growth and career. When I’m not at my desk, you’ll find me exploring nature trails, cycling through the countryside, or seeking out new physical challenges—those are my ideas of a good time! Want to start a conversation with me? Just mention BIRDS, and you’ll have my undivided attention.
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