diff --git a/.circleci/config.yml b/.circleci/config.yml
index e0be344..6db2c91 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -96,15 +96,6 @@ jobs:
     steps:
       - audit
 
-  test-node18:
-    executor:
-      name: node
-      version: '18.20'
-    steps:
-      - prepare:
-          force: true
-      - test
-
   test-node20:
     executor:
       name: node
@@ -136,9 +127,6 @@ workflows:
   test:
     jobs:
       - audit
-      - test-node18:
-          requires:
-            - audit
       - test-node20:
           requires:
             - audit
diff --git a/babel.config.js b/babel.config.js
index 9841ff6..950b939 100644
--- a/babel.config.js
+++ b/babel.config.js
@@ -1,5 +1,5 @@
 module.exports = {
   presets: [
-    ['@babel/preset-env', { targets: { node: '18' }, shippedProposals: true }],
+    ['@babel/preset-env', { targets: { node: '20' }, shippedProposals: true }],
   ],
 }
diff --git a/jest.setup.js b/jest.setup.js
index bb8f2cc..af8d02d 100644
--- a/jest.setup.js
+++ b/jest.setup.js
@@ -1,9 +1 @@
 global.context = describe
-
-// https://github.com/nodejs/undici/issues/4374
-if (process.versions.node.startsWith('18.')) {
-  const { File, Blob } = require('buffer')
-
-  global.File = File
-  global.Blob = Blob
-}
diff --git a/package.json b/package.json
index 3597303..215b0d4 100644
--- a/package.json
+++ b/package.json
@@ -27,7 +27,7 @@
     "url": "https://github.com/marp-team/marpit"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=20"
   },
   "main": "lib/index.js",
   "types": "index.d.ts",