Mithril vs Svelte
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A small JavaScript framework for building single page web apps, with routing and XHR built in.
Open source · MIT
A web UI framework whose compiler turns components into plain JavaScript that updates the page directly.
The short answer
Choose Mithril if you need…
- Developers who want a small framework with routing and HTTP utilities included
- Teams building single page apps who prefer a lightweight alternative to larger frameworks
- Projects targeting modern browsers, since the README says no polyfills are required
Choose Svelte if you need…
- Developers who want to build interactive websites with less boilerplate
- Teams building web apps who prefer a compiler-based approach
- Learners exploring how modern component frameworks work
Side-by-side
| Mithril | Svelte | |
|---|---|---|
| Type | Library | Library |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 14.5k | 88.5k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | JavaScript | JavaScript |
| Last code update | 3 months ago | 4 days ago |
What each one is
Mithril
Mithril.js is a client-side JavaScript framework for building single page applications, where the page updates in the browser without full reloads. According to its README, it is small (about 8.93 KB gzipped) and includes routing and XHR (network request) utilities without extra packages. It is installed via npm or loaded from a CDN.
Svelte
Svelte is a compiler for building web applications. You write components in a declarative style, and Svelte converts them ahead of time into efficient JavaScript that updates the page's DOM directly. It is aimed at making web interfaces simpler to write while keeping the output lightweight.
Best for
Mithril
- Developers who want a small framework with routing and HTTP utilities included
- Teams building single page apps who prefer a lightweight alternative to larger frameworks
- Projects targeting modern browsers, since the README says no polyfills are required
Svelte
- Developers who want to build interactive websites with less boilerplate
- Teams building web apps who prefer a compiler-based approach
- Learners exploring how modern component frameworks work
Strengths
Mithril
- Small size, about 8.93 KB gzipped according to the README
- Routing and XHR utilities are included out of the box
- MIT licensed with an active community on Zulip and Stack Overflow
Svelte
- MIT licensed and open source
- Compiles components to JavaScript that surgically updates the DOM, per the README
- Large community with an active Discord chat and a public roadmap
Not ideal for
Mithril
- People who need server-side rendering or a backend framework, since the README only describes client-side use
- Non-programmers looking for a no-code tool, since it requires writing JavaScript
- Projects needing support for old browsers beyond Firefox ESR and the last two versions of major browsers, per the README
Svelte
- People who need a no-code tool, since Svelte requires writing code
- Projects that must rely only on long-established tooling, because the README gives little detail on ecosystem maturity for this use
Trade-offs
Mithril
- The README does not detail the feature set beyond routing and XHR, so the scope is unclear from this source alone
- Documentation is hosted on an external site, and the README is brief
- Browser support is limited to recent versions as listed in the README
Svelte
- The README is short and defers most detail to the external website and docs
- Some setup details and requirements are not stated in the provided README
- Being a compiler-based approach, understanding the build step takes some learning
Getting started
Mithril
Install via npm
npm install mithril --saveInstall TypeScript type definitions (optional)
npm install @types/mithril --save-devSvelte
Install the svelte package (per the npm package reference in the README badges)
npm install svelteFrequently asked questions
What is the difference between Mithril and Svelte?
Mithril: A small JavaScript framework for building single page web apps, with routing and XHR built in. Svelte: A web UI framework whose compiler turns components into plain JavaScript that updates the page directly. Mithril suits developers who want a small framework with routing and http utilities included, while Svelte suits developers who want to build interactive websites with less boilerplate.
Are Mithril and Svelte free?
Mithril: Free and open source. Svelte: Free and open source.
Is Mithril or Svelte more popular?
Svelte has more GitHub stars (88.5k) than Mithril (14.5k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to Mithril and Svelte?
Other options people compare them with include React, Preact, Hyperapp, Gin, Million.js.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.