Build an AI website in 60 seconds

AI website builders let you whip up a professional website in just a few minutes, no coding skills required. That's the advantage of using an AI website builder; they handle the heavy lifting for non-technical users.

But there’s a catch: an AI website generator can produce a complete website with hidden issues that affect Core Web Vitals, weaken SEO optimization, and quietly drive visitors away. An AI-built website may look polished at first glance, yet struggle with load speed, mobile layout, or behind-the-scenes SEO details that matter to search engines and real users.

Before you connect a custom domain or share your dream website with clients, a quick performance check can prevent problems from showing up later. These seven checks focus on speed, usability, and Core Web Vitals, the signals that reveal whether your site is truly ready to launch.

The 7 must-check performance issues

Here are some of things that often run into issues and can be handled proactively:

1. Slow load speeds (images, scripts, layout)

Sometimes an AI website design generator produces oversized hero images or extra scripts that quietly slow down page speed and cause layout shifts, especially when images aren’t compressed. When a site takes too long to load, visitors lose patience fast, which can hurt engagement and reduce conversion rates before users even see your content.

To spot these issues, drop your URL into PageSpeed Insights or GTmetrix. Both tools flag problem areas right away, showing whether images, scripts, or unstable layouts are dragging performance down.

From there, lazy-load assets so images appear only as visitors scroll, then compress files to keep them lightweight. It’s a simple fix, even for non-technical users, and it often cuts load time noticeably on drag-and-drop editor sites.

2. Poor mobile responsiveness

An AI website design generator can sometimes produce sites that struggle on mobile screens. Mobile responsiveness matters because most visitors now arrive on phones, and search engines closely evaluate how layouts perform on smaller devices.

Whether you’re running an online store or a service-based business, it’s worth checking how your site behaves on mobile. Look closely at spacing, buttons, and font size to make sure stacked elements appear clean and load properly. One simple way to test this is by opening Chrome’s dev tools, switching to an iPhone view, and scrolling from top to bottom.

Some of the best AI website builders, such as B12, offer a built-in mobile preview, letting you see how your site appears on phones before launch. That small step can help your dream website feel polished and consistent across every screen.

3. Unoptimized AI-generated images

AI-generated images from a free AI website builder may sound cool at first, but they often expand file sizes into the megabytes, which slows everything on the page. Your AI prompt might produce a photorealistic hero image that looks impressive yet drags down load speed. To fix this, ditch oversized files and swap unrealistic visuals for realistic stock images or your own photos that load faster and feel more natural.

Converting images to WebP also helps, cutting file size by around 30% without visible quality loss. Tools like TinyPNG make this easy, even on free AI options. This small change alone can cut load times nearly in half, letting a polished website shine, especially for e-commerce features or landing pages built to convert.

4. Unnecessary animations or scripts

Some AI website generator tools may include animations, such as spinning loaders, hover effects, or parallax scrolling, which may appear engaging for visitors. However, this might slow down your page-loading capacity.

That’s because while these animations seem harmless, these design elements could eat up CPU power on slower devices, resulting in delayed clicks or awkward page jumps. That kind of motion rarely helps visitors understand your message or take action.

If a page feels sluggish, open your browser inspector and temporarily turn animations off. When speed improves right away, that’s your cue to reduce motion or remove scripts entirely. Extra flair from artificial intelligence can quietly double load times, while calmer pages tend to perform better in SEO-optimized content checks. Advanced AI website makers like B12 avoids this trap by default, saving you real frustration before launch.

5. Inefficient heading hierarchy affecting SEO

AI models sometimes mix up H2s and H3s, creating a heading structure that’s confusing for both readers and search engines. When headings are out of order or sections feel jumbled, visitors may get lost, and crawlers can miss relevant keywords that boost search engine optimization (SEO).

To fix this, keep one clear H1, organize main topics with H2s, and place supporting H3s underneath. Doing so improves readability, helps your AI builder showcase feature-rich sections, contact forms, client testimonials, or e-commerce functionality, and ensures your website’s purpose is clear in just a few words.

Properly structured headings make business websites or custom sites easier to scan, help websites created with built-in tools perform better, and support mobile-friendly, SEO-optimized content that can attract clients without relying on a web developer.

6. Missing technical SEO essentials

Some AI-built websites skip basic SEO elements, which makes your custom site invisible to search engines. Missing meta titles, descriptions with relevant keywords, sitemap.xml, robots.txt, canonical tags, or alt texts on images can limit visibility for business websites, online stores, or marketing agency sites.

Your AI website creator should generate meta tags, add alt text, set canonicals for duplicate content, and include internal links to guide visitors. A drag-and-drop editor or built-in tools often make this easy for non-technical users, allowing you to fine-tune without the extra cost.

These essentials ensure your fully functional website, mobile-friendly pages, and e-commerce functionality perform well in search results. With technical SEO in place, your AI builder helps your own domain attract clients, rank higher, and showcase feature-rich content efficiently.

7. Weak form or CTA functionality

Even a fully functional website can lose leads if contact forms or call-to-action (CTA) buttons fail. AI tools sometimes generate forms that don’t submit or CTAs that link nowhere, while integrations like email or calendar connections may glitch.

Test every form by sending a real submission and verifying confirmation messages. Click every CTA link, such as “Book Now” or “Get Started,” across devices to ensure they work. Ensure the integrations are connected properly so emails, sign-ups, or calendars capture information correctly.

Fixing these weak spots turns feature-rich websites into effective lead generators. Advanced AI website creators like B12 make it easy for non-technical users to fine-tune forms, capture emails, and boost conversions, letting your business websites or marketing agency site perform as intended.

How B12 ensures strong performance

B12 offers several key advantages for anyone looking to boost their business website’s performance, from fast page loading and SEO optimization to seamless business tool integration.

1. Fast hosting (TLS/HTTPS by default)

B12 websites run on reliable hosting with TLS and HTTPS enabled by default, giving your site instant credibility. Connecting a custom domain or claiming a free domain takes just a few clicks, and your websites generated are secure, fast, and ready for visitors. This setup ensures that all websites generated, from simple portfolios to full, service-based websites, launch smoothly with minimal friction.

2. Optimized templates

B12’s templates are built for speed, mobile friendliness, and clean heading structures. The drag-and-drop editor and AI Agent feature allows users to fine-tune layouts effortlessly while maintaining performance.

You get full control over design elements and content, all without the complexity often found in traditional builders. Whether creating business websites or personal projects, the builder generates sites that perfectly match your vision with user-friendly tools.

You can also explore B12’s website gallery and AI website prompt library to see the websites generated for different industries. With these features, you can find inspiration and examples of how your full website could look and function.

3. Business tools integrated natively

B12 includes built-in tools, such as intake forms, scheduling, invoicing, and payments, all natively integrated into the platform. You can launch online stores with e-commerce functionality without relying on third-party plugins that slow pages down.

Every full website benefits from streamlined workflows, whether you’re using core features or upgrading to paid plans. This approach helps turn your site into a polished, lead-generating platform with clean, single-line CTAs and consistent performance.

Conclusion

A quick performance audit can make a real difference before launch. It helps your AI-built website load faster, feel better on mobile, and send the right signals to search engines right away. Even sites created with just a few clicks deserve a final check before going live.

If you want the best AI website builder that balances speed, structure, and business AI tools without extra cost surprises, B12 stands out as an ideal option. Try B12's AI website builder today and see how you can shape a custom site in just minutes and publish a full website that feels ready for real visitors.