The table below shows the minimum browser versions Svelte's runtime and compiled output are expected to work in.
The table below shows the minimum browser versions Svelte is expected to work in, derived from the browser APIs used by Svelte's internal code.
@include .generated/browser-support.md
These numbers describe what Svelte's output _requires_ in order to run — they're derived from the APIs the code uses, not from a list of browsers the team commits to testing.
This table only covers Svelte itself. It does not include [SvelteKit](/docs/kit), other Svelte libraries, or your own code.
## What is covered
## Exceptions
- **Svelte's runtime.** Everything you import from `svelte` or its subpackages, in the form your bundler ships to the browser.
- **Compiler output.** The JavaScript the Svelte compiler emits from your `.svelte` files, including the DOM operations, bindings and transitions used in your components.
## What is not covered
- **Your own code** inside `<script>` blocks or `.svelte.js` files. If you use newer browser APIs the table will not reflect them — configure your own [browserslist](https://github.com/browserslist/browserslist) and polyfills accordingly.
- **SvelteKit**, adapters and build tooling. See the [SvelteKit docs](https://svelte.dev/docs/kit) for the browser support story there.
- **Internet Explorer 11.** Svelte's runtime relies on `Proxy`, which cannot be polyfilled. IE11 is not supported and there is no path to making it work.
## Per-feature browser requirements
Some Svelte features rely on browser APIs that exceed the floor above. The runtime still loads on older browsers — modern bundlers tree-shake the affected code when the feature is unused — but if you use one of these features, you need the higher minimum version listed here.
A few Svelte features require a higher minimum browser version. You'll only need to take the following table into consideration if you use these specific features.
@include .generated/browser-support-features.md
## How this page stays accurate
The minimum versions can only move forward in a minor or major release, and any change is recorded in the [changelog](https://github.com/sveltejs/svelte/blob/main/packages/svelte/CHANGELOG.md). Every Svelte feature — bindings, runes, directives, and module exports — is checked against the [web-features](https://www.npmjs.com/package/web-features) Baseline dataset on every pull request, and the build fails if a change requires newer browsers than the page reflects.
return`${header}\n${sep}\n${body}\n\n> [!NOTE] This equates to a <a href="https://web-platform-dx.github.io/baseline/">Baseline</a> target of ${target_label}.`;
return(
render_markdown_table(
['Browser','Minimum version'],
rows.filter(([,version])=>version!==undefined)
)+
`\n\n> [!NOTE] This equates to a <a href="https://web-platform-dx.github.io/baseline/">Baseline</a> target of ${target_label}.`
jiyujie2006
2 months ago
committed by
GitHub