diff --git a/src/wp-includes/class-wp-theme-json-resolver.php b/src/wp-includes/class-wp-theme-json-resolver.php
index b1a0d5198d67b..6b2695fe481d4 100644
--- a/src/wp-includes/class-wp-theme-json-resolver.php
+++ b/src/wp-includes/class-wp-theme-json-resolver.php
@@ -20,6 +20,19 @@
 #[AllowDynamicProperties]
 class WP_Theme_JSON_Resolver {
 
+	/**
+	 * Container for keep track of registered blocks.
+	 *
+	 * @since 6.1.0
+	 * @var array
+	 */
+	protected static $blocks_cache = array(
+		'core'   => array(),
+		'blocks' => array(),
+		'theme'  => array(),
+		'user'   => array(),
+	);
+
 	/**
 	 * Container for data coming from core.
 	 *
@@ -28,6 +41,14 @@ class WP_Theme_JSON_Resolver {
 	 */
 	protected static $core = null;
 
+	/**
+	 * Container for data coming from the blocks.
+	 *
+	 * @since 6.1.0
+	 * @var WP_Theme_JSON
+	 */
+	protected static $blocks = null;
+
 	/**
 	 * Container for data coming from the theme.
 	 *
@@ -145,6 +166,10 @@ protected static function translate( $theme_json, $domain = 'default' ) {
 	 * @return WP_Theme_JSON Entity that holds core data.
 	 */
 	public static function get_core_data() {
+		if ( null !== static::$core && static::has_same_registered_blocks( 'core' ) ) {
+			return static::$core;
+		}
+
 		$config = static::read_json_file( __DIR__ . '/theme.json' );
 		$config = static::translate( $config );
 
@@ -162,6 +187,37 @@ public static function get_core_data() {
 		return static::$core;
 	}
 
+	/**
+	 * Checks whether the registered blocks were already processed for this origin.
+	 *
+	 * @since 6.1.0
+	 *
+	 * @param string $origin Data source for which to cache the blocks.
+	 *                       Valid values are 'core', 'blocks', 'theme', and 'user'.
+	 * @return bool True on success, false otherwise.
+	 */
+	protected static function has_same_registered_blocks( $origin ) {
+		// Bail out if the origin is invalid.
+		if ( ! isset( static::$blocks_cache[ $origin ] ) ) {
+			return false;
+		}
+
+		$registry = WP_Block_Type_Registry::get_instance();
+		$blocks   = $registry->get_all_registered();
+
+		// Is there metadata for all currently registered blocks?
+		$block_diff = array_diff_key( $blocks, static::$blocks_cache[ $origin ] );
+		if ( empty( $block_diff ) ) {
+			return true;
+		}
+
+		foreach ( $blocks as $block_name => $block_type ) {
+			static::$blocks_cache[ $origin ][ $block_name ] = true;
+		}
+
+		return false;
+	}
+
 	/**
 	 * Returns the theme's data.
 	 *
@@ -189,19 +245,21 @@ public static function get_theme_data( $deprecated = array(), $options = array()
 
 		$options = wp_parse_args( $options, array( 'with_supports' => true ) );
 
-		$theme_json_data = static::read_json_file( static::get_file_path_from_theme( 'theme.json' ) );
-		$theme_json_data = static::translate( $theme_json_data, wp_get_theme()->get( 'TextDomain' ) );
+		if ( null === static::$theme || ! static::has_same_registered_blocks( 'theme' ) ) {
+			$theme_json_data = static::read_json_file( static::get_file_path_from_theme( 'theme.json' ) );
+			$theme_json_data = static::translate( $theme_json_data, wp_get_theme()->get( 'TextDomain' ) );
 
-		/**
-		 * Filters the data provided by the theme for global styles and settings.
-		 *
-		 * @since 6.1.0
-		 *
-		 * @param WP_Theme_JSON_Data Class to access and update the underlying data.
-		 */
-		$theme_json      = apply_filters( 'theme_json_theme', new WP_Theme_JSON_Data( $theme_json_data, 'theme' ) );
-		$theme_json_data = $theme_json->get_data();
-		static::$theme   = new WP_Theme_JSON( $theme_json_data );
+			/**
+			 * Filters the data provided by the theme for global styles and settings.
+			 *
+			 * @since 6.1.0
+			 *
+			 * @param WP_Theme_JSON_Data Class to access and update the underlying data.
+			 */
+			$theme_json      = apply_filters( 'theme_json_theme', new WP_Theme_JSON_Data( $theme_json_data, 'theme' ) );
+			$theme_json_data = $theme_json->get_data();
+			static::$theme   = new WP_Theme_JSON( $theme_json_data );
+		}
 
 		if ( wp_get_theme()->parent() ) {
 			// Get parent theme.json.
@@ -258,7 +316,6 @@ public static function get_theme_data( $deprecated = array(), $options = array()
 		}
 		$with_theme_supports = new WP_Theme_JSON( $theme_support_data );
 		$with_theme_supports->merge( static::$theme );
-
 		return $with_theme_supports;
 	}
 
@@ -272,7 +329,12 @@ public static function get_theme_data( $deprecated = array(), $options = array()
 	public static function get_block_data() {
 		$registry = WP_Block_Type_Registry::get_instance();
 		$blocks   = $registry->get_all_registered();
-		$config   = array( 'version' => 2 );
+
+		if ( null !== static::$blocks && static::has_same_registered_blocks( 'blocks' ) ) {
+			return static::$blocks;
+		}
+
+		$config = array( 'version' => 2 );
 		foreach ( $blocks as $block_name => $block_type ) {
 			if ( isset( $block_type->supports['__experimentalStyle'] ) ) {
 				$config['styles']['blocks'][ $block_name ] = static::remove_json_comments( $block_type->supports['__experimentalStyle'] );
@@ -298,7 +360,8 @@ public static function get_block_data() {
 		$theme_json = apply_filters( 'theme_json_blocks', new WP_Theme_JSON_Data( $config, 'blocks' ) );
 		$config     = $theme_json->get_data();
 
-		return new WP_Theme_JSON( $config, 'blocks' );
+		static::$blocks = new WP_Theme_JSON( $config, 'blocks' );
+		return static::$blocks;
 	}
 
 	/**
@@ -407,6 +470,10 @@ public static function get_user_data_from_wp_global_styles( $theme, $create_post
 	 * @return WP_Theme_JSON Entity that holds styles for user data.
 	 */
 	public static function get_user_data() {
+		if ( null !== static::$user && static::has_same_registered_blocks( 'user' ) ) {
+			return static::$user;
+		}
+
 		$config   = array();
 		$user_cpt = static::get_user_data_from_wp_global_styles( wp_get_theme() );
 
@@ -562,9 +629,18 @@ protected static function get_file_path_from_theme( $file_name, $template = fals
 	 * @since 5.8.0
 	 * @since 5.9.0 Added the `$user`, `$user_custom_post_type_id`,
 	 *              and `$i18n_schema` variables to reset.
+	 * @since 6.1.0 Added the `$blocks` and `$blocks_cache` variables
+	 *              to reset.
 	 */
 	public static function clean_cached_data() {
 		static::$core                     = null;
+		static::$blocks                   = null;
+		static::$blocks_cache             = array(
+			'core'   => array(),
+			'blocks' => array(),
+			'theme'  => array(),
+			'user'   => array(),
+		);
 		static::$theme                    = null;
 		static::$user                     = null;
 		static::$user_custom_post_type_id = null;
diff --git a/tests/phpunit/tests/theme/wpThemeJsonResolver.php b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
index 9b43a4fb33eb1..bbfffde317b31 100644
--- a/tests/phpunit/tests/theme/wpThemeJsonResolver.php
+++ b/tests/phpunit/tests/theme/wpThemeJsonResolver.php
@@ -33,6 +33,52 @@ class Tests_Theme_wpThemeJsonResolver extends WP_UnitTestCase {
 	 */
 	private $queries = array();
 
+	/**
+	 * WP_Theme_JSON_Resolver::$blocks_cache property.
+	 *
+	 * @var ReflectionProperty
+	 */
+	private static $property_blocks_cache;
+
+	/**
+	 * Original value of the WP_Theme_JSON_Resolver::$blocks_cache property.
+	 *
+	 * @var array
+	 */
+	private static $property_blocks_cache_orig_value;
+
+	/**
+	 * WP_Theme_JSON_Resolver::$core property.
+	 *
+	 * @var ReflectionProperty
+	 */
+	private static $property_core;
+
+	/**
+	 * Original value of the WP_Theme_JSON_Resolver::$core property.
+	 *
+	 * @var WP_Theme_JSON
+	 */
+	private static $property_core_orig_value;
+
+	public static function set_up_before_class() {
+		parent::set_up_before_class();
+
+		static::$property_blocks_cache = new ReflectionProperty( WP_Theme_JSON_Resolver::class, 'blocks_cache' );
+		static::$property_blocks_cache->setAccessible( true );
+		static::$property_blocks_cache_orig_value = static::$property_blocks_cache->getValue();
+
+		static::$property_core = new ReflectionProperty( WP_Theme_JSON_Resolver::class, 'core' );
+		static::$property_core->setAccessible( true );
+		static::$property_core_orig_value = static::$property_core->getValue();
+	}
+
+	public static function tear_down_after_class() {
+		static::$property_blocks_cache->setValue( WP_Theme_JSON_Resolver::class, static::$property_blocks_cache_orig_value );
+		static::$property_core->setValue( WP_Theme_JSON_Resolver::class, static::$property_core_orig_value );
+		parent::tear_down_after_class();
+	}
+
 	public function set_up() {
 		parent::set_up();
 		$this->theme_root = realpath( DIR_TESTDATA . '/themedir1' );
@@ -55,6 +101,9 @@ public function tear_down() {
 		$GLOBALS['wp_theme_directories'] = $this->orig_theme_dir;
 		wp_clean_themes_cache();
 		unset( $GLOBALS['wp_themes'] );
+
+		// Reset data between tests.
+		WP_Theme_JSON_Resolver::clean_cached_data();
 		parent::tear_down();
 	}
 
@@ -190,6 +239,198 @@ public function test_translations_are_applied() {
 		);
 	}
 
+	private function get_registered_block_names( $hard_reset = false ) {
+		static $expected_block_names;
+
+		if ( ! $hard_reset && ! empty( $expected_block_names ) ) {
+			return $expected_block_names;
+		}
+
+		$expected_block_names = array();
+		$resolver             = WP_Block_Type_Registry::get_instance();
+		$blocks               = $resolver->get_all_registered();
+		foreach ( array_keys( $blocks ) as $block_name ) {
+			$expected_block_names[ $block_name ] = true;
+		}
+
+		return $expected_block_names;
+	}
+
+	/**
+	 * Tests when WP_Theme_JSON_Resolver::$blocks_cache is empty or does not match
+	 * the all registered blocks.
+	 *
+	 * Though this is a non-public method, it is vital to other functionality.
+	 * Therefore, tests are provided to validate it functions as expected.
+	 *
+	 * @dataProvider data_has_same_registered_blocks_when_all_blocks_not_cached
+	 * @ticket 56467
+	 *
+	 * @param string $origin The origin to test.
+	 */
+	public function test_has_same_registered_blocks_when_all_blocks_not_cached( $origin, array $cache = array() ) {
+		$has_same_registered_blocks = new ReflectionMethod( WP_Theme_JSON_Resolver::class, 'has_same_registered_blocks' );
+		$has_same_registered_blocks->setAccessible( true );
+		$expected_cache = $this->get_registered_block_names();
+
+		// Set up the blocks cache for the origin.
+		$blocks_cache            = static::$property_blocks_cache->getValue();
+		$blocks_cache[ $origin ] = $cache;
+		static::$property_blocks_cache->setValue( null, $blocks_cache );
+
+		$this->assertFalse( $has_same_registered_blocks->invoke( null, $origin ), 'WP_Theme_JSON_Resolver::has_same_registered_blocks() should return false when same blocks are not cached' );
+		$blocks_cache = static::$property_blocks_cache->getValue();
+		$this->assertSameSets( $expected_cache, $blocks_cache[ $origin ], 'WP_Theme_JSON_Resolver::$blocks_cache should contain all expected block names for the given origin' );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_has_same_registered_blocks_when_all_blocks_not_cached() {
+		return array(
+			'origin: core; cache: empty'       => array(
+				'origin' => 'core',
+			),
+			'origin: blocks; cache: empty'     => array(
+				'origin' => 'blocks',
+			),
+			'origin: theme; cache: empty'      => array(
+				'origin' => 'theme',
+			),
+			'origin: user; cache: empty'       => array(
+				'origin' => 'user',
+			),
+			'origin: core; cache: not empty'   => array(
+				'origin' => 'core',
+				'cache'  => array(
+					'core/block' => true,
+				),
+			),
+			'origin: blocks; cache: not empty' => array(
+				'origin' => 'blocks',
+				'cache'  => array(
+					'core/block'    => true,
+					'core/comments' => true,
+				),
+			),
+			'origin: theme; cache: not empty'  => array(
+				'origin' => 'theme',
+				'cache'  => array(
+					'core/cover' => true,
+				),
+			),
+			'origin: user; cache: not empty'   => array(
+				'origin' => 'user',
+				'cache'  => array(
+					'core/gallery' => true,
+				),
+			),
+		);
+	}
+
+	/**
+	 * Tests when WP_Theme_JSON_Resolver::$blocks_cache is empty or does not match
+	 * the all registered blocks.
+	 *
+	 * Though this is a non-public method, it is vital to other functionality.
+	 * Therefore, tests are provided to validate it functions as expected.
+	 *
+	 * @dataProvider data_has_same_registered_blocks_when_all_blocks_are_cached
+	 * @ticket 56467
+	 *
+	 * @param string $origin The origin to test.
+	 */
+	public function test_has_same_registered_blocks_when_all_blocks_are_cached( $origin ) {
+		$has_same_registered_blocks = new ReflectionMethod( WP_Theme_JSON_Resolver::class, 'has_same_registered_blocks' );
+		$has_same_registered_blocks->setAccessible( true );
+		$expected_cache = $this->get_registered_block_names();
+
+		// Set up the cache with all registered blocks.
+		$blocks_cache            = static::$property_blocks_cache->getValue();
+		$blocks_cache[ $origin ] = $this->get_registered_block_names();
+		static::$property_blocks_cache->setValue( null, $blocks_cache );
+
+		$this->assertTrue( $has_same_registered_blocks->invoke( null, $origin ), 'WP_Theme_JSON_Resolver::has_same_registered_blocks() should return true when using the cache' );
+		$this->assertSameSets( $expected_cache, $blocks_cache[ $origin ], 'WP_Theme_JSON_Resolver::$blocks_cache should contain all expected block names for the given origin' );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_has_same_registered_blocks_when_all_blocks_are_cached() {
+		return array(
+			'core'   => array( 'core' ),
+			'blocks' => array( 'blocks' ),
+			'theme'  => array( 'theme' ),
+			'user'   => array( 'user' ),
+		);
+	}
+
+	/**
+	 * @dataProvider data_get_core_data
+	 * @covers WP_Theme_JSON_Resolver::get_core_data
+	 * @ticket 56467
+	 */
+	public function test_get_core_data( $should_fire_filter, $core_is_cached, $blocks_are_cached ) {
+		WP_Theme_JSON_Resolver::clean_cached_data();
+
+		// If should cache core, then fire the method to cache it before running the tests.
+		if ( $core_is_cached ) {
+			WP_Theme_JSON_Resolver::get_core_data();
+		}
+
+		// If should cache registered blocks, then set them up before running the tests.
+		if ( $blocks_are_cached ) {
+			$blocks_cache         = static::$property_blocks_cache->getValue();
+			$blocks_cache['core'] = $this->get_registered_block_names();
+			static::$property_blocks_cache->setValue( null, $blocks_cache );
+		}
+
+		$expected_filter_count = did_filter( 'theme_json_default' );
+		$actual                = WP_Theme_JSON_Resolver::get_core_data();
+		if ( $should_fire_filter ) {
+			$expected_filter_count++;
+		}
+
+		$this->assertSame( $expected_filter_count, did_filter( 'theme_json_default' ), 'The filter "theme_json_default" should fire the given number of times' );
+		$this->assertInstanceOf( WP_Theme_JSON::class, $actual, 'WP_Theme_JSON_Resolver::get_core_data() should return instance of WP_Theme_JSON' );
+		$this->assertSame( static::$property_core->getValue(), $actual, 'WP_Theme_JSON_Resolver::$core property should be the same object as returned from WP_Theme_JSON_Resolver::get_core_data()' );
+	}
+
+	/**
+	 * Data provider.
+	 *
+	 * @return array
+	 */
+	public function data_get_core_data() {
+		return array(
+			'When both caches are empty'     => array(
+				'should_fire_filter' => true,
+				'core_is_cached'     => false,
+				'blocks_are_cached'  => false,
+			),
+			'When the blocks_cache is not empty and matches' => array(
+				'should_fire_filter' => true,
+				'core_is_cached'     => false,
+				'blocks_are_cached'  => true,
+			),
+			'When blocks_cache is empty but core cache is not' => array(
+				'should_fire_filter' => true,
+				'core_is_cached'     => true,
+				'blocks_are_cached'  => false,
+			),
+			'When both caches are not empty' => array(
+				'should_fire_filter' => true,
+				'core_is_cached'     => true,
+				'blocks_are_cached'  => false,
+			),
+		);
+	}
+
 	/**
 	 * @ticket 52991
 	 */