diff --git a/README.md b/README.md
index 192f0b57..87ee422b 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,7 @@ See https://ebourg.github.io/jsign for more information.
 * The APPX/MSIX bundles are now signed with the correct Authenticode UUID
 * The error message displayed when the password of a PKCS#12 keystore is missing has been fixed
 * The log4j configuration warning displayed when signing a MSI file has been fixed (contributed by Pascal Davoust)
+* The value of the `storetype` parameter is now case insensitive
 * API changes:
   * The PEFile class has been refactored to keep only the methods related to signing
 
diff --git a/jsign-core/src/main/java/net/jsign/KeyStoreBuilder.java b/jsign-core/src/main/java/net/jsign/KeyStoreBuilder.java
index d06e944a..5c47c2f6 100644
--- a/jsign-core/src/main/java/net/jsign/KeyStoreBuilder.java
+++ b/jsign-core/src/main/java/net/jsign/KeyStoreBuilder.java
@@ -119,7 +119,7 @@ public KeyStoreBuilder storetype(KeyStoreType storetype) {
      */
     public KeyStoreBuilder storetype(String storetype) {
         try {
-            this.storetype = storetype != null ? KeyStoreType.valueOf(storetype) : null;
+            this.storetype = storetype != null ? KeyStoreType.valueOf(storetype.toUpperCase()) : null;
         } catch (IllegalArgumentException e) {
             String expectedTypes = Stream.of(KeyStoreType.values())
                     .filter(type -> type != NONE).map(KeyStoreType::name)
diff --git a/jsign-core/src/test/java/net/jsign/KeyStoreBuilderTest.java b/jsign-core/src/test/java/net/jsign/KeyStoreBuilderTest.java
index 6a155451..dd991f2d 100644
--- a/jsign-core/src/test/java/net/jsign/KeyStoreBuilderTest.java
+++ b/jsign-core/src/test/java/net/jsign/KeyStoreBuilderTest.java
@@ -423,4 +423,10 @@ public void testBuildPIV() throws Exception {
         KeyStore keystore = builder.build();
         assertNotNull("keystore", keystore);
     }
+
+    @Test
+    public void testLowerCaseStoreType() {
+        KeyStoreBuilder builder = new KeyStoreBuilder().storetype("pkcs12");
+        assertEquals("storetype", PKCS12, builder.storetype());
+    }
 }