diff --git a/tests/fuzzer.c b/tests/fuzzer.c
index 88f3b83f..9be92471 100644
--- a/tests/fuzzer.c
+++ b/tests/fuzzer.c
@@ -1137,6 +1137,7 @@ static int basicUnitTests(U32 const seed, double compressibility)
         size_t* const samplesSizes = (size_t*) malloc(nbSamples * sizeof(size_t));
         size_t dictSize;
         U32 dictID;
+        U32 dictHeaderSize;
 
         if (dictBuffer==NULL || samplesSizes==NULL) {
             free(dictBuffer);
@@ -1226,6 +1227,29 @@ static int basicUnitTests(U32 const seed, double compressibility)
         if (dictID==0) goto _output_error;
         DISPLAYLEVEL(3, "OK : %u \n", (unsigned)dictID);
 
+        DISPLAYLEVEL(3, "test%3i : check dict header size no error : ", testNb++);
+        dictHeaderSize = ZDICT_getDictHeaderSize(dictBuffer, dictSize);
+        if (dictHeaderSize==0) goto _output_error;
+        DISPLAYLEVEL(3, "OK : %u \n", (unsigned)dictHeaderSize);
+
+        DISPLAYLEVEL(3, "test%3i : check dict header size correctness : ", testNb++);
+        {   unsigned char const dictBufferFixed[144] = { 0x37, 0xa4, 0x30, 0xec, 0x63, 0x00, 0x00, 0x00, 0x08, 0x10, 0x00, 0x1f,
+                                                         0x0f, 0x00, 0x28, 0xe5, 0x03, 0x03, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                                                         0x00, 0x80, 0x0f, 0x9e, 0x0f, 0x00, 0x00, 0x24, 0x40, 0x80, 0x00, 0x01,
+                                                         0x02, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0xde, 0x08,
+                                                         0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+                                                         0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08,
+                                                         0x08, 0x08, 0x08, 0x08, 0xbc, 0xe1, 0x4b, 0x92, 0x0e, 0xb4, 0x7b, 0x18,
+                                                         0x86, 0x61, 0x18, 0xc6, 0x18, 0x63, 0x8c, 0x31, 0xc6, 0x18, 0x63, 0x8c,
+                                                         0x31, 0x66, 0x66, 0x66, 0x66, 0xb6, 0x6d, 0x01, 0x00, 0x00, 0x00, 0x04,
+                                                         0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x20, 0x73, 0x6f, 0x64, 0x61,
+                                                         0x6c, 0x65, 0x73, 0x20, 0x74, 0x6f, 0x72, 0x74, 0x6f, 0x72, 0x20, 0x65,
+                                                         0x6c, 0x65, 0x69, 0x66, 0x65, 0x6e, 0x64, 0x2e, 0x20, 0x41, 0x6c, 0x69 };
+            dictHeaderSize = ZDICT_getDictHeaderSize(dictBufferFixed, 144);
+            if (dictHeaderSize != 115) goto _output_error;
+        }
+        DISPLAYLEVEL(3, "OK : %u \n", (unsigned)dictHeaderSize);
+
         DISPLAYLEVEL(3, "test%3i : compress with dictionary : ", testNb++);
         cSize = ZSTD_compress_usingDict(cctx, compressedBuffer, compressedBufferSize,
                                         CNBuffer, CNBuffSize,