diff --git a/src/api.rs b/src/api.rs
index 2867fdfae3..0983b5225e 100644
--- a/src/api.rs
+++ b/src/api.rs
@@ -80,6 +80,7 @@ pub struct Inscription {
   pub children: Vec<InscriptionId>,
   pub content_length: Option<usize>,
   pub content_type: Option<String>,
+  pub effective_content_type: Option<String>,
   pub fee: u64,
   pub height: u32,
   pub id: InscriptionId,
diff --git a/src/subcommand/server.rs b/src/subcommand/server.rs
index 1522cb70bf..92de3206c3 100644
--- a/src/subcommand/server.rs
+++ b/src/subcommand/server.rs
@@ -1519,6 +1519,17 @@ impl Server {
       let info = Index::inscription_info(&index, query)?
         .ok_or_not_found(|| format!("inscription {query}"))?;
 
+      let effective_mime_type = if let Some(delegate_id) = info.inscription.delegate() {
+        let delegate_result = index.get_inscription_by_id(delegate_id);
+        if let Ok(Some(delegate)) = delegate_result {
+          delegate.content_type().map(str::to_string)
+        } else {
+          info.inscription.content_type().map(str::to_string)
+        }
+      } else {
+        info.inscription.content_type().map(str::to_string)
+      };
+
       Ok(if accept_json {
         Json(api::Inscription {
           address: info
@@ -1535,6 +1546,7 @@ impl Server {
           children: info.children,
           content_length: info.inscription.content_length(),
           content_type: info.inscription.content_type().map(|s| s.to_string()),
+          effective_content_type: effective_mime_type,
           fee: info.entry.fee,
           height: info.entry.height,
           id: info.entry.id,
diff --git a/tests/json_api.rs b/tests/json_api.rs
index abc8b635ed..ac02c1c122 100644
--- a/tests/json_api.rs
+++ b/tests/json_api.rs
@@ -160,6 +160,7 @@ fn get_inscription() {
       children: Vec::new(),
       content_length: Some(3),
       content_type: Some("text/plain;charset=utf-8".to_string()),
+      effective_content_type: Some("text/plain;charset=utf-8".to_string()),
       fee: 138,
       height: 2,
       id: inscription_id,
diff --git a/tests/wallet/inscribe.rs b/tests/wallet/inscribe.rs
index 1f35ecde7b..755e98c9ac 100644
--- a/tests/wallet/inscribe.rs
+++ b/tests/wallet/inscribe.rs
@@ -2185,6 +2185,39 @@ fn file_inscribe_with_delegate_inscription() {
   ord_rpc_server.assert_response(format!("/content/{}", inscribe.inscriptions[0].id), "FOO");
 }
 
+#[test]
+fn inscription_with_delegate_returns_effective_content_type() {
+  let bitcoin_rpc_server = test_bitcoincore_rpc::spawn();
+  let ord_rpc_server = TestServer::spawn_with_server_args(&bitcoin_rpc_server, &[], &[]);
+  create_wallet(&bitcoin_rpc_server, &ord_rpc_server);
+
+  bitcoin_rpc_server.mine_blocks(1);
+  let (delegate, _) = inscribe(&bitcoin_rpc_server, &ord_rpc_server);
+
+  let inscribe = CommandBuilder::new(format!(
+    "wallet inscribe --fee-rate 1.0 --delegate {delegate} --file meow.wav"
+  ))
+  .write("meow.wav", [0; 2048])
+  .bitcoin_rpc_server(&bitcoin_rpc_server)
+  .ord_rpc_server(&ord_rpc_server)
+  .run_and_deserialize_output::<Inscribe>();
+
+  bitcoin_rpc_server.mine_blocks(1);
+
+  let inscription_id = inscribe.inscriptions[0].id;
+  let json_response = ord_rpc_server.json_request(format!("/inscription/{}", inscription_id));
+
+  let inscription_json: api::Inscription =
+    serde_json::from_str(&json_response.text().unwrap()).unwrap();
+  assert_regex_match!(inscription_json.address.unwrap(), r"bc1p.*");
+
+  assert_eq!(inscription_json.content_type, Some("audio/wav".to_string()));
+  assert_eq!(
+    inscription_json.effective_content_type,
+    Some("text/plain;charset=utf-8".to_string())
+  );
+}
+
 #[test]
 fn file_inscribe_with_non_existent_delegate_inscription() {
   let bitcoin_rpc_server = test_bitcoincore_rpc::spawn();