Svelte 4 End of Life
Support dates and upgrade guidance — rebuilt from live data.
End of Life
Svelte 4 reached end of life on 19 Oct 2024. It no longer receives security fixes.
716 days without security patches
Recommended action: upgrade to Svelte 5. Check your versionnpm list svelte
Support timeline
Official dates from the Svelte release process.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 22 Jun 2023 | 3y 3mo ago |
| Security Support ended | 19 Oct 2024 | 2y ago |
| Latest release | 4.2.20 · 20 May 2025 | final |
Where to go from 4
Recommended target: Svelte 5.
The newest actively supported branch is Svelte 5 (latest release 5.57.1).
Frequently asked questions
Is Svelte 4 still safe to use?
Svelte 4 reached end of life on 19 Oct 2024, 716 days ago, and is no longer covered by standard support. Running it means no guaranteed security fixes.
Can I still download Svelte 4?
Yes — the final release (4.2.20) generally remains available from vendor archives and OS package mirrors, but installing it means running software with known, unpatched vulnerabilities.
What should I upgrade Svelte 4 to?
Upgrade to Svelte 5, the newest actively supported branch.