diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 744a075..06ece16 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -12,7 +12,7 @@ on:
     - cron: '45 4 * * *'
 
 env:
-  crystal_version: 1.20.3
+  crystal_version: 1.21.0
   shards_version: 0.20.0
   gc_version: 8.2.12
 
diff --git a/alpine/Dockerfile b/alpine/Dockerfile
index 362eaed..19131b1 100644
--- a/alpine/Dockerfile
+++ b/alpine/Dockerfile
@@ -22,7 +22,7 @@ RUN tar zxf bdwgc.tar.gz && \
     make install
 
 # Build crystal
-ARG crystal_version=1.20.0
+ARG crystal_version=1.21.0
 ARG crystal_src_url=https://github.com/crystal-lang/crystal/archive/${crystal_version}.tar.gz
 ADD ${crystal_src_url} crystal.tar.gz
 RUN tar zxf crystal.tar.gz && \
diff --git a/centos/Dockerfile b/centos/Dockerfile
index 2266d4c..f3e8df9 100644
--- a/centos/Dockerfile
+++ b/centos/Dockerfile
@@ -1,6 +1,6 @@
 ARG base_image=quay.io/centos/centos
 ARG base_image_tag=stream9
-ARG crystal_version=1.20.0
+ARG crystal_version=1.21.0
 
 # Copy the statically compiled compiler from this image
 FROM --platform=$BUILDPLATFORM 84codes/crystal:latest-alpine AS alpine
diff --git a/debian/Dockerfile b/debian/Dockerfile
index 8e31948..57d53ca 100644
--- a/debian/Dockerfile
+++ b/debian/Dockerfile
@@ -29,7 +29,7 @@ RUN tar zxf bdwgc.tar.gz && \
     make install
 
 # Build crystal
-ARG crystal_version=1.20.0
+ARG crystal_version=1.21.0
 ARG crystal_src_url=https://github.com/crystal-lang/crystal/archive/${crystal_version}.tar.gz
 ADD ${crystal_src_url} crystal.tar.gz
 RUN tar zxf crystal.tar.gz && \
diff --git a/fedora/Dockerfile b/fedora/Dockerfile
index 4a9ba8d..7a08f79 100644
--- a/fedora/Dockerfile
+++ b/fedora/Dockerfile
@@ -24,7 +24,7 @@ RUN rpmdev-setuptree
 WORKDIR /root/rpmbuild
 COPY crystal.spec /root/rpmbuild/SPECS/
 
-ARG crystal_version=1.20.0
+ARG crystal_version=1.21.0
 ARG shards_version=0.20.0
 ARG pkg_revision=1