Ruby 4.0 End of Life
Support dates, the patch stream you lose at EOL, and upgrade guidance — rebuilt from live data.
Ruby 4.0 is actively supported. It reaches end of life on 31 Mar 2029.
Support timeline
Official dates from the Ruby release process.
| Milestone | Date | Status |
|---|---|---|
| Initial release | 25 Dec 2025 | — |
| End of life (scheduled) | 31 Mar 2029 | in 965 days |
| Latest release | 4.0.6 · 13 Jul 2026 | current |
What you lose on 31 Mar 2029
Being supported means fixes keep shipping to this branch. Here is the stream that stops. Source: NVD.
Ruby CVEs published and patched, by year
1 published in the last 12 months · data refreshed 2026-08-09
At the last-12-month rate of 1 Ruby CVEs, running 4.0 for a year past 31 Mar 2029 means roughly that many vulnerabilities fixed upstream but never backported to your branch. Past branches bear this out: Ruby 3.2 has missed 1 since it went end of life.
How much runway a newer branch buys
Ruby 4.0 is the newest branch — this is the longest runway currently available.
| Branch | End of life | Days left | vs 4.0 |
|---|---|---|---|
| Ruby 4.0 | 31 Mar 2029 | 965 | this branch |
| Ruby 3.4 | 31 Mar 2028 | 600 | -365 days |
| Ruby 3.3 | 31 Mar 2027 | 234 | -731 days |
Review ruby-lang.org.
Frequently asked questions
When does Ruby 4.0 reach end of life?
Ruby 4.0 reaches end of life on 31 Mar 2029 — 965 days from now. After that date it receives no security fixes.
Is Ruby 4.0 still supported?
Yes. Ruby 4.0 is currently maintained. Latest release: 4.0.6, published 13 Jul 2026.
What happens when Ruby 4.0 reaches end of life?
Security fixes stop. Over the last 12 months 1 Ruby vulnerabilities were published and patched across supported branches; once 4.0 is end of life, fixes at that rate no longer reach it.
How long do I have to upgrade from Ruby 4.0?
965 days. This is already the newest branch, so this is the longest runway currently available.