diff --git a/aquatic_http/src/lib.rs b/aquatic_http/src/lib.rs
index 9a58b18..7f9fc65 100644
--- a/aquatic_http/src/lib.rs
+++ b/aquatic_http/src/lib.rs
@@ -92,6 +92,7 @@ pub fn run(config: Config) -> ::anyhow::Result<()> {
                     request_mesh_builder,
                     priv_dropper,
                     server_start_instant,
+                    i,
                 )
                 .await
             })
@@ -122,6 +123,7 @@ pub fn run(config: Config) -> ::anyhow::Result<()> {
                     state,
                     request_mesh_builder,
                     server_start_instant,
+                    i,
                 )
                 .await
             })
diff --git a/aquatic_http/src/workers/socket.rs b/aquatic_http/src/workers/socket.rs
index af55e3c..3c1ac49 100644
--- a/aquatic_http/src/workers/socket.rs
+++ b/aquatic_http/src/workers/socket.rs
@@ -39,6 +39,9 @@ const RESPONSE_HEADER_A: &[u8] = b"HTTP/1.1 200 OK\r\nContent-Length: ";
 const RESPONSE_HEADER_B: &[u8] = b"        ";
 const RESPONSE_HEADER_C: &[u8] = b"\r\n\r\n";
 
+#[cfg(feature = "metrics")]
+thread_local! { static WORKER_INDEX: ::std::cell::Cell<usize> = Default::default() }
+
 static RESPONSE_HEADER: Lazy<Vec<u8>> =
     Lazy::new(|| [RESPONSE_HEADER_A, RESPONSE_HEADER_B, RESPONSE_HEADER_C].concat());
 
@@ -60,7 +63,11 @@ pub async fn run_socket_worker(
     request_mesh_builder: MeshBuilder<ChannelRequest, Partial>,
     priv_dropper: PrivilegeDropper,
     server_start_instant: ServerStartInstant,
+    worker_index: usize,
 ) {
+    #[cfg(feature = "metrics")]
+    WORKER_INDEX.with(|index| index.set(worker_index));
+
     let config = Rc::new(config);
     let access_list = state.access_list;
 
@@ -105,6 +112,7 @@ pub async fn run_socket_worker(
                                 "aquatic_active_connections",
                                 1.0,
                                 "ip_version" => ip_version_str,
+                                "worker_index" => worker_index.to_string(),
                             );
 
                             let result = Connection::run(
@@ -124,6 +132,7 @@ pub async fn run_socket_worker(
                                 "aquatic_active_connections",
                                 1.0,
                                 "ip_version" => ip_version_str,
+                                "worker_index" => worker_index.to_string(),
                             );
 
                             result
@@ -319,7 +328,8 @@ impl Connection {
                 ::metrics::increment_counter!(
                     "aquatic_requests_total",
                     "type" => "announce",
-                    "ip_version" => peer_addr_to_ip_version_str(&self.peer_addr)
+                    "ip_version" => peer_addr_to_ip_version_str(&self.peer_addr),
+                    "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
                 );
 
                 let info_hash = request.info_hash;
@@ -365,7 +375,8 @@ impl Connection {
                 ::metrics::increment_counter!(
                     "aquatic_requests_total",
                     "type" => "scrape",
-                    "ip_version" => peer_addr_to_ip_version_str(&self.peer_addr)
+                    "ip_version" => peer_addr_to_ip_version_str(&self.peer_addr),
+                    "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
                 );
 
                 let mut info_hashes_by_worker: BTreeMap<usize, Vec<InfoHash>> = BTreeMap::new();
@@ -507,6 +518,7 @@ impl Connection {
                 "aquatic_responses_total",
                 "type" => response_type,
                 "ip_version" => peer_addr_to_ip_version_str(&self.peer_addr),
+                "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
             );
         }
 
diff --git a/aquatic_http/src/workers/swarm.rs b/aquatic_http/src/workers/swarm.rs
index c2a2c6a..76893ad 100644
--- a/aquatic_http/src/workers/swarm.rs
+++ b/aquatic_http/src/workers/swarm.rs
@@ -27,6 +27,9 @@ use aquatic_http_protocol::response::*;
 use crate::common::*;
 use crate::config::Config;
 
+#[cfg(feature = "metrics")]
+thread_local! { static WORKER_INDEX: ::std::cell::Cell<usize> = Default::default() }
+
 pub trait Ip: ::std::fmt::Debug + Copy + Eq + ::std::hash::Hash {
     #[cfg(feature = "metrics")]
     fn ip_version_str() -> &'static str;
@@ -177,6 +180,7 @@ impl TorrentMaps {
             "aquatic_peers",
             total_num_peers,
             "ip_version" => I::ip_version_str(),
+            "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
         );
 
         torrent_map.shrink_to_fit();
@@ -189,7 +193,11 @@ pub async fn run_swarm_worker(
     state: State,
     request_mesh_builder: MeshBuilder<ChannelRequest, Partial>,
     server_start_instant: ServerStartInstant,
+    worker_index: usize,
 ) {
+    #[cfg(feature = "metrics")]
+    WORKER_INDEX.with(|index| index.set(worker_index));
+
     let (_, mut request_receivers) = request_mesh_builder.join(Role::Consumer).await.unwrap();
 
     let torrents = Rc::new(RefCell::new(TorrentMaps::default()));
@@ -222,18 +230,20 @@ pub async fn run_swarm_worker(
     // Periodically update torrent count metrics
     #[cfg(feature = "metrics")]
     TimerActionRepeat::repeat(enclose!((config, torrents) move || {
-        enclose!((config, torrents) move || async move {
+        enclose!((config, torrents, worker_index) move || async move {
             let torrents = torrents.borrow_mut();
 
             ::metrics::gauge!(
                 "aquatic_torrents",
                 torrents.ipv4.len() as f64,
-                "ip_version" => "4"
+                "ip_version" => "4",
+                "worker_index" => worker_index.to_string(),
             );
             ::metrics::gauge!(
                 "aquatic_torrents",
                 torrents.ipv6.len() as f64,
-                "ip_version" => "6"
+                "ip_version" => "6",
+                "worker_index" => worker_index.to_string(),
             );
 
             Some(Duration::from_secs(config.metrics.torrent_count_update_interval))
@@ -425,14 +435,16 @@ pub fn upsert_peer_and_get_response_peers<I: Ip>(
             ::metrics::decrement_gauge!(
                 "aquatic_peers",
                 1.0,
-                "ip_version" => I::ip_version_str()
+                "ip_version" => I::ip_version_str(),
+                "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
             );
         }
         PeerStatus::Leeching | PeerStatus::Seeding if opt_removed_peer.is_none() => {
             ::metrics::increment_gauge!(
                 "aquatic_peers",
                 1.0,
-                "ip_version" => I::ip_version_str()
+                "ip_version" => I::ip_version_str(),
+                "worker_index" => WORKER_INDEX.with(|index| index.get()).to_string(),
             );
         }
         _ => {}