diff --git a/test/fuzz/modp_toupper_fuzzer.c b/test/fuzz/modp_toupper_fuzzer.c
new file mode 100644
index 0000000..19af5c2
--- /dev/null
+++ b/test/fuzz/modp_toupper_fuzzer.c
@@ -0,0 +1,23 @@
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "modp_ascii.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        if(size<3){
+                return 0;
+        }
+
+        char *new_str = (char *)malloc(size+1);
+        if (new_str == NULL){
+                return 0;
+        }
+        memcpy(new_str, data, size);
+        new_str[size] = '\0';
+
+        modp_toupper(new_str, size);
+
+        free(new_str);
+        return 1;
+}
diff --git a/test/fuzz/modp_utf8_validate_fuzzer.c b/test/fuzz/modp_utf8_validate_fuzzer.c
new file mode 100644
index 0000000..58c51f1
--- /dev/null
+++ b/test/fuzz/modp_utf8_validate_fuzzer.c
@@ -0,0 +1,23 @@
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "modp_utf8.h"
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        if(size<3){
+                return 0;
+        }
+
+        char *new_str = (char *)malloc(size+1);
+        if (new_str == NULL){
+                return 0;
+        }
+        memcpy(new_str, data, size);
+        new_str[size] = '\0';
+
+        modp_utf8_validate(new_str, size);
+
+        free(new_str);
+        return 1;
+}
diff --git a/test/fuzz/modp_xml_decode_fuzzer3.c b/test/fuzz/modp_xml_decode_fuzzer3.c
new file mode 100644
index 0000000..41c5395
--- /dev/null
+++ b/test/fuzz/modp_xml_decode_fuzzer3.c
@@ -0,0 +1,17 @@
+#include <stdint.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "modp_xml.h"
+
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
+        if(size<3){
+                return 0;
+        }
+
+        size_t d = 0;
+        char buf[size+1];
+        d = modp_xml_decode(buf, (char*)data, size);
+        return 1;
+}