Lucide vs Fluent vs Material Icons - Which Should You Use?

2024-11-08

When you're building a Power App and need icons, you've got options. Lucide, Fluent, Material, Bootstrap, and probably a dozen other icon libraries. They all have thousands of icons, they're all free, and they all technically work in Power Apps. So which one should you actually use?

The answer isn't "it doesn't matter" or "use whatever you like." The icon library you choose affects how your app looks, how users perceive it, and whether your design feels cohesive or messy. Let me break down the three most popular libraries and when each one makes sense.

Lucide Icons - The modern minimalist

Lucide started as a fork of Feather Icons and has grown into one of the best icon libraries out there. The style is clean, minimal, and modern. Every icon is outlined with consistent stroke widths, and they all feel like they belong to the same family.

The visual aesthetic is very web 2.0 in the best way. Not flashy, not trying to be clever, just clean and functional. If you've seen apps like Linear, Vercel, or any modern SaaS product, you've probably seen Lucide icons or something similar.

What I like about Lucide is the consistency. Every icon follows the same design language. Rounded corners, 2px default stroke width, centered in a 24x24 viewBox. When you use Lucide throughout your app, everything looks cohesive without you having to think about it.

The library is also huge. Over 1,500 icons covering pretty much everything you'd need. Common stuff like home, search, and settings, but also specific icons for things like database, git branch, and calendar. If you need an icon, Lucide probably has it.

Performance-wise, Lucide icons are optimized and lightweight. The SVG code is clean, there's no unnecessary bloat, and they render fast even on slower devices.

When to use Lucide: If you're building a modern, minimal Power App that doesn't need to match Microsoft's design language. Especially good for internal tools, productivity apps, dashboards, or anything where you want a clean, professional look. Also great if you're building something that might extend beyond Power Apps to the web, because Lucide has excellent React and Vue components.

When not to use Lucide: If your app needs to feel like a native Microsoft product, Lucide might look out of place. It's very clearly not Microsoft's design language, which can be good or bad depending on context.

Fluent Icons - The Microsoft native

Fluent is Microsoft's design system, and Fluent icons are what you see throughout Office 365, Teams, SharePoint, and all of Microsoft's modern products. If you've used any Microsoft app in the last few years, you know these icons.

The style is more rounded and softer than Lucide. Icons have a friendly, approachable feel. Stroke widths are consistent, corners are rounded, and everything is designed to work well at different sizes. Microsoft clearly put a lot of thought into making these icons work across their entire ecosystem.

What's interesting about Fluent is that it comes in multiple styles. Filled, outlined, two-tone, and more. This gives you flexibility to show different states or create visual hierarchy. For example, you might use outlined icons for inactive states and filled icons for active states.

The library is massive. Over 2,500 icons covering everything from basic UI elements to specific Microsoft product features. If you need an icon for Excel, Teams, SharePoint, or any other Microsoft service, Fluent has official icons for them.

Using Fluent in Power Apps makes sense because you're already in the Microsoft ecosystem. Your app sits next to Teams, SharePoint, and Office. Using the same icons helps your app feel native rather than like a third-party tool bolted on.

When to use Fluent: If your Power App integrates with Microsoft 365, if it's used alongside Teams or SharePoint, or if you want your app to feel like a native Microsoft product. Fluent icons signal "this belongs here" to users who spend their day in Microsoft tools. Also great if you need filled and outlined variants for showing different states.

When not to use Fluent: If you're building something that should feel distinct from Microsoft's ecosystem. Maybe you're building a consumer-facing app or something with its own strong brand identity. Fluent icons are so recognizably Microsoft that they bring that association with them.

Material Icons - The Google standard

Material icons come from Google's Material Design system. If you've used any Google product (Gmail, Drive, Android apps), you've seen these icons everywhere. They're the standard for Android development and a lot of web apps that follow Material Design principles.

The style is slightly more geometric than Lucide or Fluent. Icons tend to have sharper angles and more defined shapes. The aesthetic is clean but less soft than Fluent, more structured than Lucide. It's a distinctive look that immediately signals "Material Design" to anyone familiar with it.

Like Fluent, Material icons come in multiple variants. Outlined, filled, rounded, sharp, and two-tone. This gives you a lot of flexibility in how you use them. You can mix variants to create hierarchy or stick with one style for consistency.

The library is huge. Over 2,000 icons covering pretty much everything. Google has been building this library for years, so there are icons for things you didn't even know you needed icons for.

Performance is solid. Google optimized these icons for Android apps, which means they're lightweight and render efficiently. They work great in Power Apps without any special handling.

When to use Material: If your Power App has a connection to Google services, if you're targeting Android users specifically, or if you want a design that feels modern but not Microsoft-specific. Material icons are neutral enough to work in most contexts while still having a distinct personality. Also good if you're building something consumer-facing where Google's design language is more familiar than Microsoft's.

When not to use Material: If you're deep in the Microsoft ecosystem. Material icons in a Teams-integrated Power App feel off. It's not wrong, but it creates a subtle disconnect. Users expect Microsoft's design language in Microsoft tools.

The actual differences that matter

Let's talk about the practical differences beyond aesthetics.

Icon coverage: All three libraries are comprehensive, but they have different strengths. Fluent has the best coverage for Microsoft-specific features (Teams, SharePoint, Office apps). Material has great coverage for Google services and Android concepts. Lucide has excellent coverage for web development concepts (git, terminal, code). Check all three if you need something specific.

Variants and states: Fluent and Material both offer multiple variants (filled, outlined, etc.). Lucide is outline-only. If you need to show selected vs unselected states with filled vs outlined icons, Lucide won't work. You'd need to mix libraries or use a different approach.

File size and performance: Lucide icons tend to be the smallest and cleanest. Fluent and Material are slightly larger but still very efficient. In practice, the difference is negligible unless you're loading hundreds of icons, which you shouldn't be doing anyway.

Design coherence: Lucide feels the most cohesive to me. Every icon clearly belongs to the same family. Fluent and Material are also consistent, but because they're older and maintained by massive organizations, there are occasional inconsistencies where newer icons don't quite match older ones.

Future-proofing: Lucide is open source and community-driven, so new icons get added regularly based on actual needs. Fluent and Material are controlled by Microsoft and Google respectively, so new icons come when those companies decide to add them. All three are actively maintained, so you're safe either way.

My recommendation

Here's what I actually use and recommend.

If you're building a Power App that integrates with Microsoft 365, use Fluent. Your users are already in Teams, SharePoint, and Office. Fluent icons make your app feel like it belongs there. The familiarity helps with adoption because users instinctively understand the visual language.

If you're building an internal tool that's standalone or doesn't integrate heavily with Microsoft services, use Lucide. It looks modern and professional without being tied to any specific company's design language. This is what I use for most projects.

If you're building something consumer-facing or connected to Google services, consider Material. It's familiar to a huge audience, especially mobile users, and it signals "modern app" without saying "Microsoft."

Don't mix libraries unless you have a really good reason. I've seen apps that use Lucide for some icons, Fluent for others, and Material for a few more. It looks bad. Pick one library and stick with it. Consistency matters more than having the perfect icon for every situation.

What about Bootstrap Icons?

Bootstrap Icons deserve a mention. They're solid, they're comprehensive (over 2,000 icons), and they're free. The style is similar to Lucide but slightly less refined. If you're already using Bootstrap in your web projects, they're a natural choice.

For Power Apps specifically, I'd still lean toward Lucide, Fluent, or Material because they're more actively maintained and have better tooling around them. But Bootstrap Icons work fine if you prefer them.

Testing your choice

Before you commit to a library, test it in your actual app. Add a few icons to a screen, customize the colors to match your theme, and see how they feel. Do they look right with your fonts and layout? Do they match the vibe you're going for?

Show your app to users and get feedback. Do the icons feel intuitive? Can users quickly identify what each icon means? If there's confusion, it might be the icons, or it might be that you need to add text labels.

Using PowerIcons to compare

This is exactly why PowerIcons supports multiple libraries. You can browse Lucide, Fluent, Material, and Bootstrap all in one place. Search for "home" and see how each library interprets it. Pick the one that fits your app best.

You can even try different libraries in your app without committing. Copy a Lucide home icon, see how it looks, then swap it for a Fluent home icon and compare. Once you've decided which library feels right, stick with it for the entire app.

Making your final choice

At the end of the day, the "right" icon library is the one that makes your app look cohesive and professional. That usually means matching your context.

Building for Microsoft 365? Use Fluent. Building a modern internal tool? Use Lucide. Building something consumer-facing or Google-adjacent? Use Material.

And whatever you choose, use it consistently. Don't switch libraries mid-project because you found one icon you like better. Consistency beats having the perfect individual icons every time.

The good news is that all three libraries are excellent. You can't really go wrong. Just make a choice, stick with it, and focus on building something useful. Your users care way more about whether your app solves their problem than about which icon library you used.