diff --git a/src/modules/ellswift/tests_impl.h b/src/modules/ellswift/tests_impl.h
index 3c314c9b50..7625276362 100644
--- a/src/modules/ellswift/tests_impl.h
+++ b/src/modules/ellswift/tests_impl.h
@@ -405,31 +405,22 @@ void run_ellswift_tests(void) {
 
     /* Test hash initializers. */
     {
-        secp256k1_sha256 sha, sha_optimized;
-        static const unsigned char encode_tag[] = {'s', 'e', 'c', 'p', '2', '5', '6', 'k', '1', '_', 'e', 'l', 'l', 's', 'w', 'i', 'f', 't', '_', 'e', 'n', 'c', 'o', 'd', 'e'};
-        static const unsigned char create_tag[] = {'s', 'e', 'c', 'p', '2', '5', '6', 'k', '1', '_', 'e', 'l', 'l', 's', 'w', 'i', 'f', 't', '_', 'c', 'r', 'e', 'a', 't', 'e'};
-        static const unsigned char bip324_tag[] = {'b', 'i', 'p', '3', '2', '4', '_', 'e', 'l', 'l', 's', 'w', 'i', 'f', 't', '_', 'x', 'o', 'n', 'l', 'y', '_', 'e', 'c', 'd', 'h'};
-
-        /* Check that hash initialized by
-         * secp256k1_ellswift_sha256_init_encode has the expected
-         * state. */
-        secp256k1_sha256_initialize_tagged(&sha, encode_tag, sizeof(encode_tag));
-        secp256k1_ellswift_sha256_init_encode(&sha_optimized);
-        test_sha256_eq(&sha, &sha_optimized);
-
-        /* Check that hash initialized by
-         * secp256k1_ellswift_sha256_init_create has the expected
-         * state. */
-        secp256k1_sha256_initialize_tagged(&sha, create_tag, sizeof(create_tag));
-        secp256k1_ellswift_sha256_init_create(&sha_optimized);
-        test_sha256_eq(&sha, &sha_optimized);
-
-        /* Check that hash initialized by
-         * secp256k1_ellswift_sha256_init_bip324 has the expected
-         * state. */
-        secp256k1_sha256_initialize_tagged(&sha, bip324_tag, sizeof(bip324_tag));
-        secp256k1_ellswift_sha256_init_bip324(&sha_optimized);
-        test_sha256_eq(&sha, &sha_optimized);
+        secp256k1_sha256 sha_optimized;
+        {
+            unsigned char tag[] = "secp256k1_ellswift_encode";
+            secp256k1_ellswift_sha256_init_encode(&sha_optimized);
+            sha256_tag_test_internal(&sha_optimized, (unsigned char*)tag, sizeof(tag) - 1);
+        }
+        {
+            unsigned char tag[] = "secp256k1_ellswift_create";
+            secp256k1_ellswift_sha256_init_create(&sha_optimized);
+            sha256_tag_test_internal(&sha_optimized, (unsigned char*)tag, sizeof(tag) - 1);
+        }
+        {
+            unsigned char tag[] = "bip324_ellswift_xonly_ecdh";
+            secp256k1_ellswift_sha256_init_bip324(&sha_optimized);
+            sha256_tag_test_internal(&sha_optimized, (unsigned char*)tag, sizeof(tag) - 1);
+        }
     }
 }
 
diff --git a/src/modules/musig/tests_impl.h b/src/modules/musig/tests_impl.h
index 4694c31a32..2be6a88f5b 100644
--- a/src/modules/musig/tests_impl.h
+++ b/src/modules/musig/tests_impl.h
@@ -548,12 +548,6 @@ static void musig_nonce_test(void) {
     }
 }
 
-static void sha256_tag_test_internal(secp256k1_sha256 *sha_tagged, unsigned char *tag, size_t taglen) {
-    secp256k1_sha256 sha;
-    secp256k1_sha256_initialize_tagged(&sha, tag, taglen);
-    test_sha256_eq(&sha, sha_tagged);
-}
-
 /* Checks that the initialized tagged hashes have the expected
  * state. */
 static void sha256_tag_test(void) {
diff --git a/src/modules/schnorrsig/tests_impl.h b/src/modules/schnorrsig/tests_impl.h
index 2d716a01f8..401f33c6a4 100644
--- a/src/modules/schnorrsig/tests_impl.h
+++ b/src/modules/schnorrsig/tests_impl.h
@@ -21,11 +21,8 @@ static void nonce_function_bip340_bitflip(unsigned char **args, size_t n_flip, s
 }
 
 static void run_nonce_function_bip340_tests(void) {
-    unsigned char tag[] = {'B', 'I', 'P', '0', '3', '4', '0', '/', 'n', 'o', 'n', 'c', 'e'};
-    unsigned char aux_tag[] = {'B', 'I', 'P', '0', '3', '4', '0', '/', 'a', 'u', 'x'};
     unsigned char algo[] = {'B', 'I', 'P', '0', '3', '4', '0', '/', 'n', 'o', 'n', 'c', 'e'};
     size_t algolen = sizeof(algo);
-    secp256k1_sha256 sha;
     secp256k1_sha256 sha_optimized;
     unsigned char nonce[32], nonce_z[32];
     unsigned char msg[32];
@@ -36,19 +33,17 @@ static void run_nonce_function_bip340_tests(void) {
     unsigned char *args[5];
     int i;
 
-    /* Check that hash initialized by
-     * secp256k1_nonce_function_bip340_sha256_tagged has the expected
-     * state. */
-    secp256k1_sha256_initialize_tagged(&sha, tag, sizeof(tag));
-    secp256k1_nonce_function_bip340_sha256_tagged(&sha_optimized);
-    test_sha256_eq(&sha, &sha_optimized);
-
-   /* Check that hash initialized by
-    * secp256k1_nonce_function_bip340_sha256_tagged_aux has the expected
-    * state. */
-    secp256k1_sha256_initialize_tagged(&sha, aux_tag, sizeof(aux_tag));
-    secp256k1_nonce_function_bip340_sha256_tagged_aux(&sha_optimized);
-    test_sha256_eq(&sha, &sha_optimized);
+    /* Check that the initialized tagged hashes have the expected state */
+    {
+        unsigned char tag[] = "BIP0340/nonce";
+        secp256k1_nonce_function_bip340_sha256_tagged(&sha_optimized);
+        sha256_tag_test_internal(&sha_optimized, tag, sizeof(tag) - 1);
+    }
+    {
+        unsigned char tag[] = "BIP0340/aux";
+        secp256k1_nonce_function_bip340_sha256_tagged_aux(&sha_optimized);
+        sha256_tag_test_internal(&sha_optimized, tag, sizeof(tag) - 1);
+    }
 
     testrand256(msg);
     testrand256(key);
@@ -158,13 +153,11 @@ static void test_schnorrsig_api(void) {
 /* Checks that hash initialized by secp256k1_schnorrsig_sha256_tagged has the
  * expected state. */
 static void test_schnorrsig_sha256_tagged(void) {
-    unsigned char tag[] = {'B', 'I', 'P', '0', '3', '4', '0', '/', 'c', 'h', 'a', 'l', 'l', 'e', 'n', 'g', 'e'};
-    secp256k1_sha256 sha;
+    unsigned char tag[] = "BIP0340/challenge";
     secp256k1_sha256 sha_optimized;
 
-    secp256k1_sha256_initialize_tagged(&sha, (unsigned char *) tag, sizeof(tag));
     secp256k1_schnorrsig_sha256_tagged(&sha_optimized);
-    test_sha256_eq(&sha, &sha_optimized);
+    sha256_tag_test_internal(&sha_optimized, tag, sizeof(tag) - 1);
 }
 
 /* Helper function for schnorrsig_bip_vectors
diff --git a/src/tests.c b/src/tests.c
index 0f7b0d4c4c..b3836e793b 100644
--- a/src/tests.c
+++ b/src/tests.c
@@ -609,6 +609,13 @@ static void test_sha256_eq(const secp256k1_sha256 *sha1, const secp256k1_sha256
     CHECK(sha1->bytes == sha2->bytes);
     CHECK(secp256k1_memcmp_var(sha1->s, sha2->s, sizeof(sha1->s)) == 0);
 }
+/* Convenience function for using test_sha256_eq to verify the correctness of a
+ * tagged hash midstate. This function is used by some module tests. */
+static void sha256_tag_test_internal(secp256k1_sha256 *sha_tagged, unsigned char *tag, size_t taglen) {
+    secp256k1_sha256 sha;
+    secp256k1_sha256_initialize_tagged(&sha, tag, taglen);
+    test_sha256_eq(&sha, sha_tagged);
+}
 
 static void run_hmac_sha256_tests(void) {
     static const char *keys[6] = {