diff --git a/tests/phpunit/tests/speculative-loading/wpPrintSpeculationRules.php b/tests/phpunit/tests/speculative-loading/wpPrintSpeculationRules.php
index e2887f8b0b6ce..12d8a7edcee79 100644
--- a/tests/phpunit/tests/speculative-loading/wpPrintSpeculationRules.php
+++ b/tests/phpunit/tests/speculative-loading/wpPrintSpeculationRules.php
@@ -52,9 +52,9 @@ static function () {
 		);
 
 		$output = get_echo( 'wp_print_speculation_rules' );
-		$this->assertStringContainsString( '<script type="speculationrules">', $output );
+		$this->assertStringContainsString( '<script type="application/speculationrules+json">', $output );
 
-		$json  = str_replace( array( '<script type="speculationrules">', '</script>' ), '', $output );
+		$json  = str_replace( array( '<script type="application/speculationrules+json"', '</script>' ), '', $output );
 		$rules = json_decode( $json, true );
 		$this->assertIsArray( $rules );
 		$this->assertArrayHasKey( 'prerender', $rules );