diff --git a/nostrdb/src/block.c b/nostrdb/src/block.c
index c2ef49d2..ec06b810 100644
--- a/nostrdb/src/block.c
+++ b/nostrdb/src/block.c
@@ -201,3 +201,10 @@ struct nostr_bech32 *ndb_bech32_block(struct ndb_block *block) {
 size_t ndb_blocks_total_size(struct ndb_blocks *blocks) {
 	return blocks->total_size;
 }
+
+void ndb_blocks_free(struct ndb_blocks *blocks) {
+	if ((blocks->flags & NDB_BLOCK_FLAG_OWNED) != NDB_BLOCK_FLAG_OWNED)
+		return;
+
+	free(blocks);
+}
diff --git a/nostrdb/src/block.h b/nostrdb/src/block.h
index 93c98821..0af32d0b 100644
--- a/nostrdb/src/block.h
+++ b/nostrdb/src/block.h
@@ -9,11 +9,14 @@
 #include "nostrdb.h"
 #include <inttypes.h>
 
+#define NDB_BLOCK_FLAG_OWNED 1
+
 #pragma pack(push, 1)
 
 struct ndb_blocks {
 	unsigned char version;
-	unsigned char padding[3];
+	unsigned char flags;
+	unsigned char padding[2];
 
 	uint32_t words;
 	uint32_t num_blocks;
diff --git a/nostrdb/src/content_parser.c b/nostrdb/src/content_parser.c
index 6c961bb8..a83ba933 100644
--- a/nostrdb/src/content_parser.c
+++ b/nostrdb/src/content_parser.c
@@ -536,6 +536,7 @@ int ndb_parse_content(unsigned char *buf, int buf_size,
 	parser.blocks->words = 0;
 	parser.blocks->num_blocks = 0;
 	parser.blocks->blocks_size = 0;
+	parser.blocks->flags = 0;
 
 	blocks_start = start = parser.content.p;
 	while (parser.content.p < parser.content.end) {
diff --git a/nostrdb/src/nostrdb.h b/nostrdb/src/nostrdb.h
index 6eae9fee..05039a6d 100644
--- a/nostrdb/src/nostrdb.h
+++ b/nostrdb/src/nostrdb.h
@@ -471,6 +471,8 @@ int ndb_parse_content(unsigned char *buf, int buf_size,
 enum ndb_block_type ndb_block_type(struct ndb_blocks *blocks);
 size_t ndb_blocks_total_size(struct ndb_blocks *blocks);
 
+/// Free blocks if they are owned, safe to call on unowned blocks as well.
+void ndb_blocks_free(struct ndb_blocks *blocks);
 
 
 // BLOCK ITERATORS