diff --git a/src/db.rs b/src/db.rs
index f65969e..17896c2 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -55,9 +55,10 @@ impl Database {
             );
 
             -- Main table with normalized foreign keys and integer timestamp
+            -- timestamp_ms stores milliseconds since epoch for uniqueness
             CREATE TABLE IF NOT EXISTS signature_entries (
                 session_id TEXT NOT NULL,
-                timestamp INTEGER NOT NULL,
+                timestamp_ms INTEGER NOT NULL,
                 app_id INTEGER NOT NULL REFERENCES apps(id),
                 version_id INTEGER NOT NULL REFERENCES versions(id),
                 offline_login_usage INTEGER,
@@ -70,7 +71,7 @@ impl Database {
                 model_id INTEGER REFERENCES models(id),
                 device_id INTEGER REFERENCES devices(id),
                 password_autofill_usage INTEGER,
-                PRIMARY KEY (session_id, timestamp)
+                PRIMARY KEY (session_id, timestamp_ms)
             ) WITHOUT ROWID;
 
             CREATE INDEX IF NOT EXISTS idx_session_id ON signature_entries(session_id);
@@ -96,7 +97,7 @@ impl Database {
         let mut insert_stmt = tx.prepare_cached(
             r#"
             INSERT INTO signature_entries (
-                session_id, timestamp, app_id, version_id,
+                session_id, timestamp_ms, app_id, version_id,
                 offline_login_usage, is_password_autofill_enabled, camera_roll_usage,
                 os_id, app_name_id, touch_id, is_offline_login_enabled,
                 model_id, device_id, password_autofill_usage
@@ -114,7 +115,7 @@ impl Database {
 
             insert_stmt.execute(params![
                 entry.session_id,
-                entry.timestamp.and_utc().timestamp(),
+                entry.timestamp_ms,
                 app_id,
                 version_id,
                 entry.offline_login_usage,
diff --git a/src/parser.rs b/src/parser.rs
index c447fae..b663776 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -7,7 +7,8 @@ use std::sync::LazyLock;
 #[derive(Debug, Clone, PartialEq)]
 pub struct SignatureEntry {
     pub session_id: String,
-    pub timestamp: NaiveDateTime,
+    /// Timestamp as milliseconds since Unix epoch (UTC)
+    pub timestamp_ms: i64,
     pub app: String,
     pub version: String,
     pub offline_login_usage: Option<i64>,
@@ -39,7 +40,7 @@ pub enum ParsedMessage {
 static SESSION_ID_RE: LazyLock<Regex> =
     LazyLock::new(|| Regex::new(r"sessionId=([^,\s]+)").unwrap());
 static DATETIME_RE: LazyLock<Regex> =
-    LazyLock::new(|| Regex::new(r#"dt="(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2})"#).unwrap());
+    LazyLock::new(|| Regex::new(r#"dt="(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2})(?:,(\d{3}))?"#).unwrap());
 static CORRELATION_ID_RE: LazyLock<Regex> =
     LazyLock::new(|| Regex::new(r"correlationId=([^,\s]+)").unwrap());
 static SIGNATURE_RE: LazyLock<Regex> =
@@ -84,15 +85,8 @@ impl SignatureParser {
             .map(|m| m.as_str().to_string())
             .ok_or_else(|| anyhow!("Missing sessionId"))?;
 
-        // Extract timestamp
-        let datetime_str = DATETIME_RE
-            .captures(line)
-            .and_then(|c| c.get(1))
-            .map(|m| m.as_str())
-            .ok_or_else(|| anyhow!("Missing datetime"))?;
-
-        let timestamp = NaiveDateTime::parse_from_str(datetime_str, "%Y-%m-%d %H:%M:%S")
-            .map_err(|e| anyhow!("Invalid datetime format: {}", e))?;
+        // Extract timestamp as milliseconds
+        let timestamp_ms = extract_timestamp_ms(line)?;
 
         // Extract signature details
         let caps = SIGNATURE_RE
@@ -109,7 +103,7 @@ impl SignatureParser {
 
         let entry = SignatureEntry {
             session_id,
-            timestamp,
+            timestamp_ms,
             app,
             version,
             offline_login_usage: parse_number(&details, "offlineLoginUsage"),
@@ -143,7 +137,7 @@ impl MessageParser for MobileClientIosParser {
 
 impl MobileClientIosParser {
     fn parse_mobile_ios_line(&self, line: &str) -> Result<ParsedMessage> {
-        let timestamp = extract_timestamp(line)?;
+        let timestamp_ms = extract_timestamp_ms(line)?;
         let session_id = extract_correlation_id(line)?;
 
         let caps = MOBILE_IOS_RE
@@ -158,7 +152,7 @@ impl MobileClientIosParser {
 
         let entry = SignatureEntry {
             session_id,
-            timestamp,
+            timestamp_ms,
             app,
             version,
             offline_login_usage: None,
@@ -192,7 +186,7 @@ impl MessageParser for MobileClientAndroidParser {
 
 impl MobileClientAndroidParser {
     fn parse_mobile_android_line(&self, line: &str) -> Result<ParsedMessage> {
-        let timestamp = extract_timestamp(line)?;
+        let timestamp_ms = extract_timestamp_ms(line)?;
         let session_id = extract_correlation_id(line)?;
 
         let caps = MOBILE_ANDROID_RE
@@ -207,7 +201,7 @@ impl MobileClientAndroidParser {
 
         let entry = SignatureEntry {
             session_id,
-            timestamp,
+            timestamp_ms,
             app,
             version,
             offline_login_usage: None,
@@ -226,16 +220,22 @@ impl MobileClientAndroidParser {
     }
 }
 
-/// Extract timestamp from log line
-fn extract_timestamp(line: &str) -> Result<NaiveDateTime> {
-    let datetime_str = DATETIME_RE
+/// Extract timestamp from log line as milliseconds since Unix epoch
+fn extract_timestamp_ms(line: &str) -> Result<i64> {
+    let caps = DATETIME_RE
         .captures(line)
-        .and_then(|c| c.get(1))
-        .map(|m| m.as_str())
         .ok_or_else(|| anyhow!("Missing datetime"))?;
 
-    NaiveDateTime::parse_from_str(datetime_str, "%Y-%m-%d %H:%M:%S")
-        .map_err(|e| anyhow!("Invalid datetime format: {}", e))
+    let datetime_str = caps.get(1).map(|m| m.as_str()).unwrap();
+    let millis: i64 = caps
+        .get(2)
+        .map(|m| m.as_str().parse().unwrap_or(0))
+        .unwrap_or(0);
+
+    let dt = NaiveDateTime::parse_from_str(datetime_str, "%Y-%m-%d %H:%M:%S")
+        .map_err(|e| anyhow!("Invalid datetime format: {}", e))?;
+
+    Ok(dt.and_utc().timestamp_millis() + millis)
 }
 
 /// Extract correlation ID as session ID for mobile client logs