diff --git a/src/eckey.h b/src/eckey.h
index d54d44c9..3ebe8969 100644
--- a/src/eckey.h
+++ b/src/eckey.h
@@ -16,6 +16,10 @@
 
 static int secp256k1_eckey_pubkey_parse(secp256k1_ge *elem, const unsigned char *pub, size_t size);
 static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *pub, size_t *size, int compressed);
+/** Serialize a group element (that is not allowed to be infinity) to a compressed public key (33 bytes). */
+static void secp256k1_eckey_pubkey_serialize33(secp256k1_ge *elem, unsigned char *pub33);
+/** Serialize a group element (that is not allowed to be infinity) to an uncompressed public key (65 bytes). */
+static void secp256k1_eckey_pubkey_serialize65(secp256k1_ge *elem, unsigned char *pub65);
 
 static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar *key, const secp256k1_scalar *tweak);
 static int secp256k1_eckey_pubkey_tweak_add(secp256k1_ge *key, const secp256k1_scalar *tweak);
diff --git a/src/eckey_impl.h b/src/eckey_impl.h
index a88a5964..4f647607 100644
--- a/src/eckey_impl.h
+++ b/src/eckey_impl.h
@@ -55,6 +55,25 @@ static int secp256k1_eckey_pubkey_serialize(secp256k1_ge *elem, unsigned char *p
     return 1;
 }
 
+static void secp256k1_eckey_pubkey_serialize33(secp256k1_ge *elem, unsigned char *pub33) {
+    VERIFY_CHECK(!secp256k1_ge_is_infinity(elem));
+
+    secp256k1_fe_normalize_var(&elem->x);
+    secp256k1_fe_normalize_var(&elem->y);
+    pub33[0] = secp256k1_fe_is_odd(&elem->y) ? SECP256K1_TAG_PUBKEY_ODD : SECP256K1_TAG_PUBKEY_EVEN;
+    secp256k1_fe_get_b32(&pub33[1], &elem->x);
+}
+
+static void secp256k1_eckey_pubkey_serialize65(secp256k1_ge *elem, unsigned char *pub65) {
+    VERIFY_CHECK(!secp256k1_ge_is_infinity(elem));
+
+    secp256k1_fe_normalize_var(&elem->x);
+    secp256k1_fe_normalize_var(&elem->y);
+    pub65[0] = SECP256K1_TAG_PUBKEY_UNCOMPRESSED;
+    secp256k1_fe_get_b32(&pub65[1], &elem->x);
+    secp256k1_fe_get_b32(&pub65[33], &elem->y);
+}
+
 static int secp256k1_eckey_privkey_tweak_add(secp256k1_scalar *key, const secp256k1_scalar *tweak) {
     secp256k1_scalar_add(key, key, tweak);
     return !secp256k1_scalar_is_zero(key);