Flutter Web in Production: Lessons Learned

Back to Blog

We've been using Flutter Web in production since 2022, well before many agencies were willing to take the plunge. After deploying 15+ web applications built with Flutter, we have a nuanced view: it's incredibly powerful for the right use cases, and a poor fit for others. This is our honest, no-hype assessment.

Where Flutter Web Shines

Internal Dashboards & Admin Panels

This is Flutter Web's sweet spot. Internal tools don't need SEO, initial load time is less critical (users bookmark them), and the rich widget library makes data-heavy UIs a breeze. We've built CRM dashboards, analytics platforms, and inventory management systems that our clients rave about.

Web Apps (Not Websites)

If your product is a web application — something users log into and interact with deeply — Flutter Web excels. Think project management tools, design editors, collaborative workspaces. The consistent experience across mobile and web is a genuine differentiator.

PWAs (Progressive Web Apps)

Flutter Web with PWA support means you can build once and have an installable app on all platforms. For B2B products where app store overhead is unwanted, this is perfect.

Where It Struggles

SEO-Dependent Content Sites

Let's be real: Flutter Web renders content using Canvas (CanvasKit) or HTML elements. While Google can now index JavaScript-rendered content, Flutter Web's SEO story is still weaker than traditional HTML/CSS. If organic search traffic is your primary acquisition channel, consider a hybrid approach or a different tech.

"We made the mistake of building a content-heavy marketing site in Flutter Web. After 6 months, we rebuilt it in plain HTML/CSS for SEO. The Flutter web app now serves as the logged-in dashboard only." — Lesson from one of our early projects

Initial Load Time

Flutter Web's initial payload is significant. The CanvasKit renderer alone adds ~2MB to the first load. For web apps where users return frequently (the app gets cached), this is fine. For landing pages where first impression matters, it's a problem.

Our mitigation strategies:

Use the HTML renderer for text-heavy content (smaller payload)
Implement deferred loading for non-critical features
Show a branded loading screen while Flutter initializes
Use CDN edge caching aggressively

Text Selection & Accessibility

With the CanvasKit renderer, text isn't real DOM text — it's painted on a canvas. This historically broke text selection, screen readers, and browser find (Ctrl+F). Flutter has made significant progress here with the SelectionArea widget and semantic rendering, but it's still not perfect.

Performance Benchmarks

From our last 5 production Flutter Web apps (all using CanvasKit):

First Contentful Paint: 2.1 - 3.8 seconds (depending on payload)
Time to Interactive: 3.5 - 5.2 seconds
Subsequent loads: 0.5 - 1.2 seconds (cached)
Lighthouse Performance Score: 55-75 (first load), 90+ (cached)

Compare this to React/Next.js apps that typically achieve 1.5-2.5s TTI. Flutter Web is slower on first load but comparable on subsequent visits.

Our Hybrid Approach

For most client projects, we now recommend a hybrid strategy:

Marketing/landing pages: Traditional HTML/CSS/JS (fast, SEO-friendly)
App experience (dashboard, features): Flutter Web
Mobile apps: Flutter (shared codebase with web)

This gives you the best of both worlds: fast, indexable marketing pages and a rich, cross-platform application experience.

Technical Tips for Flutter Web

1. Choose Your Renderer Wisely

// Use HTML renderer for text-heavy, SEO-needs
flutter build web --web-renderer html

// Use CanvasKit for rich visuals, animations
flutter build web --web-renderer canvaskit

// Auto-select based on device (default)
flutter build web --web-renderer auto

2. Implement Deferred Loading

Split your app into chunks that load on demand. The settings page doesn't need to be downloaded before the user even logs in.

3. Optimize Assets

Use --tree-shake-icons flag to remove unused Material icons
Compress all images to WebP format
Lazy-load images below the fold
Use FontManifest.json to subset fonts

4. Handle Browser Back Button

Flutter Web's default back button behavior can be confusing. Implement proper route management with GoRouter and handle browser history explicitly.

The Verdict: When to Use Flutter Web

✅ Use Flutter Web when:

Building web applications (not websites), internal tools, dashboards, PWAs, or when sharing code with mobile Flutter apps. Users interact deeply, return frequently, and SEO isn't the primary traffic driver.

❌ Don't use Flutter Web when:

Building content/marketing sites, blogs, e-commerce storefronts, or any project where SEO and initial page load speed are critical success metrics.

Looking Ahead

Flutter Web is improving rapidly. The Wasm (WebAssembly) compilation target, which landed in Flutter 3.22, dramatically improves load times. The multi-view embedding API allows mixing Flutter widgets into existing web pages. And the Impeller rendering engine promises better web performance.

We're bullish on Flutter Web's future, but pragmatic about its present. Choose the right tool for the right job, and you'll build great products.

Have questions about whether Flutter Web is right for your project? We offer free consultations to help you decide.