diff --git a/src/NzbDrone.Common/OAuth/OAuthTools.cs b/src/NzbDrone.Common/OAuth/OAuthTools.cs
index 866890966..65aea8489 100644
--- a/src/NzbDrone.Common/OAuth/OAuthTools.cs
+++ b/src/NzbDrone.Common/OAuth/OAuthTools.cs
@@ -99,7 +99,7 @@ public static string GetTimestamp(DateTime dateTime)
 
         private static long ToUnixTime(DateTime dateTime)
         {
-            var timeSpan = dateTime - new DateTime(1970, 1, 1);
+            var timeSpan = dateTime - DateTime.UnixEpoch;
             var timestamp = (long)timeSpan.TotalSeconds;
 
             return timestamp;
diff --git a/src/NzbDrone.Core/Parser/DateTimeUtil.cs b/src/NzbDrone.Core/Parser/DateTimeUtil.cs
index 71f243c66..4a00a220f 100644
--- a/src/NzbDrone.Core/Parser/DateTimeUtil.cs
+++ b/src/NzbDrone.Core/Parser/DateTimeUtil.cs
@@ -27,17 +27,13 @@ public static DateTime UnixTimestampToDateTime(long unixTime)
 
         public static DateTime UnixTimestampToDateTime(double unixTime)
         {
-            var unixStart = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
             var unixTimeStampInTicks = (long)(unixTime * TimeSpan.TicksPerSecond);
-            return new DateTime(unixStart.Ticks + unixTimeStampInTicks);
+            return new DateTime(DateTime.UnixEpoch.Ticks + unixTimeStampInTicks, DateTimeKind.Utc);
         }
 
         public static double DateTimeToUnixTimestamp(DateTime dt)
         {
-            var date = dt.ToUniversalTime();
-            var ticks = date.Ticks - new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc).Ticks;
-            var ts = ticks / TimeSpan.TicksPerSecond;
-            return ts;
+            return (double)new DateTimeOffset(dt.ToUniversalTime()).ToUnixTimeSeconds();
         }
 
         // ex: "2 hours 1 day"