diff --git a/converter-comparison/run.sh b/converter-comparison/run.sh
index 9547905..c756818 100755
--- a/converter-comparison/run.sh
+++ b/converter-comparison/run.sh
@@ -2,7 +2,7 @@
 # Keep these versions and --before in step with the README's comparison table.
 set -eu
 here=$(cd "$(dirname "$0")" && pwd)
-node_image=node:24.22.1-alpine3.24
+node_image=node:26.12.1-alpine3.24
 docker run --rm --ulimit core=0 -u "$(id -u):$(id -g)" -e HOME=/tmp -v "$here:/comparison:ro" -w /tmp \
   "$node_image" sh -c '
     npm install --before=2026-10-15 --ignore-scripts --no-audit --no-fund --silent \
diff --git a/docker-runner.sh b/docker-runner.sh
index c096905..2a0f236 100644
--- a/docker-runner.sh
+++ b/docker-runner.sh
@@ -4,7 +4,7 @@ bun_image=oven/bun:1.4.4-alpine
 deno_image=denoland/deno:2.9.8
 firefox_image=selenium/standalone-firefox:155.0.1
 floor_image=node:18.20.8-alpine3.21
-node_image=node:24.22.1-alpine3.24
+node_image=node:26.12.1-alpine3.24
 
 in_image() {
   local image=$1 entrypoint=$2
diff --git a/package-lock.json b/package-lock.json
index 077dd18..94f1b6e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -9,7 +9,7 @@
       "version": "0.2.0",
       "license": "MIT",
       "devDependencies": {
-        "@types/node": "24.19.2",
+        "@types/node": "26.6.5",
         "fast-check": "4.10.2",
         "oxlint": "1.90.0",
         "typescript": "7.0.2"
@@ -366,13 +366,13 @@
       }
     },
     "node_modules/@types/node": {
-      "version": "24.19.2",
-      "resolved": "https://registry.npmjs.org/@types/node/-/node-24.19.2.tgz",
-      "integrity": "sha512-93d49wCWJkCyN87MxLpNN6KXPCwFw7bVUg79mGUV1OS40JGWwVCr8n61DXCSqz7CV6/VfPkb7xec7uP2M+QHWQ==",
+      "version": "26.6.5",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-26.6.5.tgz",
+      "integrity": "sha512-uMzsv9stDdofIZBx4UGh4Z9ZgXnGC9seRDscilBcTHAeOFk67MZg/k9bWVfO+bk4qZmG+l52hRnLwUiH2LnJTg==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "undici-types": ">=7.24.0 <7.24.7"
+        "undici-types": "~8.9.0"
       }
     },
     "node_modules/@typescript/typescript-aix-ppc64": {
@@ -840,9 +840,9 @@
       }
     },
     "node_modules/undici-types": {
-      "version": "7.24.6",
-      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.24.6.tgz",
-      "integrity": "sha512-WRNW+sJgj5OBN4/0JpHFqtqzhpbnV0GuB+OozA9gCL7a993SmU+1JBZCzLNxYsbMfIeDL+lTsphD5jN5N+n0zg==",
+      "version": "8.9.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-8.9.0.tgz",
+      "integrity": "sha512-KTDyRTYX8sWmKXAikPHHSyc63CRPETMctyjKFupcC6OBLXT3xsN0e9aF7m+mIXutFWpUXuedtowG7iLOzp0kQg==",
       "dev": true,
       "license": "MIT"
     }
diff --git a/package.json b/package.json
index 8c54b6d..ee82aba 100644
--- a/package.json
+++ b/package.json
@@ -48,7 +48,7 @@
     "typecheck": "tsc --noEmit && tsc --noEmit -p tsconfig.build.json"
   },
   "devDependencies": {
-    "@types/node": "24.19.2",
+    "@types/node": "26.6.5",
     "fast-check": "4.10.2",
     "oxlint": "1.90.0",
     "typescript": "7.0.2"