> ## Documentation Index
> Fetch the complete documentation index at: https://withlooksy.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Will Virtual Try-On Slow Down My Store?

> No, Looksy is optimized for minimal performance impact. Learn how virtual try-on maintains fast page speeds and passes Core Web Vitals.

## No, Looksy Won't Slow Down Your Store

Looksy is engineered for **zero performance impact** on your Shopify store. Page speed remains fast, and your Core Web Vitals scores stay in the green.

## How Looksy Maintains Fast Performance

<CardGroup cols={2}>
  <Card title="Lazy Loading" icon="hourglass">
    Button loads only when needed, not on page load
  </Card>

  <Card title="Async JavaScript" icon="code">
    Doesn't block page rendering
  </Card>

  <Card title="Minimal File Size" icon="compress">
    Optimized code bundle (\< 50KB)
  </Card>

  <Card title="CDN Delivery" icon="server">
    Fast global loading from edge servers
  </Card>
</CardGroup>

## Performance Metrics

### Before vs. After Looksy Installation

Typical performance impact:

| Metric                       | Before Looksy | After Looksy | Change        |
| ---------------------------- | ------------- | ------------ | ------------- |
| **Page Load Time**           | 2.1s          | 2.1s         | **No change** |
| **Time to Interactive**      | 3.2s          | 3.3s         | **+0.1s**     |
| **First Contentful Paint**   | 1.5s          | 1.5s         | **No change** |
| **Largest Contentful Paint** | 2.4s          | 2.4s         | **No change** |
| **Cumulative Layout Shift**  | 0.05          | 0.05         | **No change** |

<Check>
  Looksy adds negligible overhead – typically less than 100ms to overall page interaction time.
</Check>

## Core Web Vitals Compatibility

Looksy is designed to pass Google's Core Web Vitals:

### LCP (Largest Contentful Paint)

**Target:** \< 2.5 seconds

**Looksy impact:** None. The button loads after LCP element (main product image).

### FID (First Input Delay)

**Target:** \< 100ms

**Looksy impact:** Minimal (\< 10ms). Async loading prevents blocking.

### CLS (Cumulative Layout Shift)

**Target:** \< 0.1

**Looksy impact:** None. Button has reserved space, no unexpected shifts.

<Tip>
  Run Google PageSpeed Insights before and after installing Looksy. You'll see scores remain virtually identical.
</Tip>

## How Virtual Try-On Actually Works

### On Page Load

**What happens:**

1. Page loads normally
2. Looksy button placeholder is added
3. JavaScript loads **asynchronously** (doesn't block rendering)
4. Button becomes functional

**Time to functional:** \< 1 second after page load

### When Customer Clicks "Try On"

**What happens:**

1. Modal opens instantly (\< 0.5s)
2. Camera/upload UI loads
3. Customer uploads photo
4. Image is sent to Looksy servers for processing
5. Result returns in 15-20 seconds

**Processing happens on Looksy servers, not your store.**

### After Try-On Completes

**What happens:**

* Result displays
* Customer closes modal
* Normal shopping continues
* No residual impact on page performance

## Shopify Performance Best Practices

Looksy follows all Shopify performance guidelines:

<AccordionGroup>
  <Accordion title="App Embed Architecture">
    Looksy uses Shopify's app embed system, which is optimized for performance. Apps load after critical page content, ensuring fast initial page loads.
  </Accordion>

  <Accordion title="Minimal DOM Manipulation">
    Looksy adds minimal HTML to your page (just the button). The try-on modal loads only when clicked, avoiding unnecessary DOM bloat.
  </Accordion>

  <Accordion title="No Third-Party Dependencies">
    Looksy doesn't load jQuery or other heavy libraries. All code is custom-built and lightweight.
  </Accordion>

  <Accordion title="Image Optimization">
    Any images loaded by Looksy (like result renders) are optimized and compressed for fast delivery.
  </Accordion>
</AccordionGroup>

## Comparing to Other Apps

### Looksy vs. Average Shopify App

| Feature                      | Looksy   | Average App        |
| ---------------------------- | -------- | ------------------ |
| **File size**                | \< 50KB  | 200-500KB          |
| **Loading method**           | Async    | Often synchronous  |
| **Render blocking**          | No       | Often yes          |
| **Core Web Vitals impact**   | Minimal  | Can be significant |
| **Performance optimization** | Built-in | Variable           |

<Note>
  Many Shopify apps negatively impact performance. Looksy is specifically engineered to avoid this.
</Note>

## Real-World Performance Data

### Merchant Results

Typical feedback from Looksy customers:

* **"No noticeable change in page speed after installation"**
* **"PageSpeed score stayed at 90+"**
* **"Core Web Vitals still passing"**
* **"Mobile performance is great"**

### A/B Test Results

Stores that A/B tested pages with and without Looksy found:

* **Page load time difference:** \< 0.1 seconds
* **Bounce rate:** No change or slight improvement (customers engage more)
* **SEO rankings:** Unaffected (no performance penalty)

## Mobile Performance

### Mobile-Specific Optimizations

Mobile performance is equally strong:

* **4G/5G:** No noticeable delay
* **3G:** Gracefully handles slower connections
* **Slow networks:** Button still loads, try-on may take slightly longer (processing is server-side)

### Mobile Metrics

Typical mobile performance:

| Metric                | Mobile (4G)    |
| --------------------- | -------------- |
| **Button load time**  | \< 1 second    |
| **Modal open time**   | \< 0.5 seconds |
| **Try-on processing** | 15-20 seconds  |
| **Total interaction** | \< 7 seconds   |

## Testing Your Store's Performance

### Before Installing Looksy

1. Visit [Google PageSpeed Insights](https://pagespeed.web.dev/)
2. Test a product page URL
3. Note your scores (Performance, LCP, FID, CLS)
4. Screenshot for comparison

### After Installing Looksy

1. Wait 24 hours (for caching)
2. Test the same product page
3. Compare scores
4. Verify minimal or no change

<Check>
  If you see a performance decrease, it's likely due to other factors (new apps, theme changes, image issues). Contact support for help.
</Check>

## What Doesn't Impact Performance

### Common Misconceptions

**"Adding any app slows down my store"**

* Not true. Well-built apps like Looksy have minimal impact.

**"Virtual try-on requires heavy processing on my site"**

* False. Processing happens on Looksy servers, not your store.

**"The try-on button loads on every page"**

* No. It only loads on enabled product pages, not sitewide.

**"Modal interactions slow down browsing"**

* No. The modal is only active when opened by the customer.

## What Actually Slows Down Stores

If you notice performance issues, check these common culprits:

1. **Large unoptimized product images** (> 1MB)
2. **Too many apps** (> 15-20)
3. **Heavy theme code** (bloated themes)
4. **Third-party scripts** (analytics, ads)
5. **Unoptimized videos** (autoplay videos)

<Warning>
  Don't blame Looksy for performance issues that existed before installation. Use PageSpeed Insights to identify actual bottlenecks.
</Warning>

## SEO and Page Speed

### Google Ranking Factors

Google uses page speed as a ranking factor. Will Looksy hurt SEO?

**No.**

* Looksy has **minimal performance impact**
* Core Web Vitals remain in "Good" range
* No negative SEO effect
* May even **improve** engagement metrics (time on site, lower bounce rate)

### Engagement Metrics Improvement

Stores with Looksy often see:

* **Lower bounce rate** (customers engage more)
* **Higher time on page** (using try-on)
* **More pages per session** (try on multiple products)

These **positive engagement signals** can actually help SEO.

## Monitoring Ongoing Performance

### What to Track

* **Google PageSpeed Insights scores** (monthly check)
* **Shopify Online Store Speed Report**
* **Core Web Vitals in Google Search Console**
* **Real user metrics** (via Google Analytics)

### Performance Troubleshooting

If you notice performance issues:

1. **Test without Looksy** (disable app temporarily)
2. **Check other recently installed apps**
3. **Review theme updates** (themes can cause slowdowns)
4. **Optimize product images** (compress, use WebP)
5. **Contact Looksy support** if issues persist

## Common Questions

<AccordionGroup>
  <Accordion title="Will Looksy affect my SEO rankings?">
    No. Looksy has minimal performance impact and doesn't hurt SEO. Improved engagement metrics (lower bounce rate, higher time on site) may even help SEO.
  </Accordion>

  <Accordion title="Does the try-on processing happen on my server?">
    No. All AI processing happens on Looksy servers. Your Shopify store only handles displaying the button and result – no heavy lifting.
  </Accordion>

  <Accordion title="What if I have many other apps installed?">
    Looksy won't add to app bloat issues. However, if your store is already slow due to too many apps, consider removing underperforming ones to improve overall speed.
  </Accordion>

  <Accordion title="Can I test performance before committing?">
    Yes. Install Looksy, run PageSpeed Insights tests, and verify performance is acceptable. If you're not satisfied, uninstall within your trial period.
  </Accordion>
</AccordionGroup>

## Performance Best Practices

To maintain fast page speeds with Looksy:

* [ ] Optimize product images (compress, use WebP format)
* [ ] Limit total apps to \< 20
* [ ] Use a lightweight, performance-optimized theme
* [ ] Enable Shopify CDN for image delivery
* [ ] Monitor Core Web Vitals regularly
* [ ] Remove unused apps and theme code
* [ ] Use lazy loading for images
* [ ] Minimize third-party scripts

<Check>
  Following these practices ensures your store stays fast, with or without Looksy.
</Check>

## The Bottom Line

**Will Looksy slow down your store?**

**No.** Looksy is purpose-built for zero performance impact:

* Async loading (doesn't block rendering)
* Minimal file size (\< 50KB)
* Lazy loading (loads only when needed)
* Server-side processing (no client-side strain)
* CDN delivery (fast global loading)
* Core Web Vitals compliant

**Your store will remain fast, your SEO won't suffer, and your customers will enjoy a great experience.**

## Next Steps

<CardGroup cols={2}>
  <Card title="Performance Troubleshooting" icon="gauge" href="/troubleshooting/performance">
    Fix performance issues and optimize speed
  </Card>

  <Card title="Mobile Optimization" icon="mobile" href="/integration/mobile-optimization">
    Ensure fast mobile experience
  </Card>

  <Card title="Best Practices" icon="star" href="/product-setup/best-practices">
    Optimize your setup for maximum performance
  </Card>

  <Card title="Pricing & Plans" icon="dollar-sign" href="/faq/pricing-and-plans">
    See Looksy pricing options
  </Card>
</CardGroup>