diff --git a/CHANGELOG.md b/CHANGELOG.md
index d02f371..bcc3b3d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 
 For a full diff see [`1.2.0...main`][1.2.0...main].
 
+### Changed
+
+- Allowed installation of PHP 8.4 ([#318]), by [@localheinz]
+
 ## [`1.2.0`][1.2.0]
 
 For a full diff see [`1.1.0...1.2.0`][1.1.0..1.2.0].
@@ -61,5 +65,6 @@ For a full diff see [`c020e6f...1.0.0`][c020e6f...1.0.0].
 [#151]: https://github.com/ergebnis/json/pull/151
 [#226]: https://github.com/ergebnis/json/pull/226
 [#227]: https://github.com/ergebnis/json/pull/227
+[#318]: https://github.com/ergebnis/json/pull/318
 
 [@localheinz]: https://github.com/localheinz
diff --git a/composer.json b/composer.json
index 7fb0232..511da71 100644
--- a/composer.json
+++ b/composer.json
@@ -20,7 +20,7 @@
     "security": "https://github.com/ergebnis/json/blob/main/.github/SECURITY.md"
   },
   "require": {
-    "php": "~7.4.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0",
+    "php": "~7.4.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0",
     "ext-json": "*"
   },
   "require-dev": {
diff --git a/composer.lock b/composer.lock
index 2423cab..50efa0a 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "c3862d19c0ef15fbf85bfb552361eb46",
+    "content-hash": "35375cd96aaad4c90152bf6228ab0d89",
     "packages": [],
     "packages-dev": [
         {
@@ -6654,7 +6654,7 @@
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {
-        "php": "~7.4.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0",
+        "php": "~7.4.0 || ~8.0.0 || ~8.1.0 || ~8.2.0 || ~8.3.0 || ~8.4.0",
         "ext-json": "*"
     },
     "platform-dev": [],