diff --git a/source/Ox/js/Format.js b/source/Ox/js/Format.js
index 595eb2ab..12eed55e 100644
--- a/source/Ox/js/Format.js
+++ b/source/Ox/js/Format.js
@@ -159,7 +159,10 @@ Ox.formatDate = function(date, str, utc) {
         ['p', function(d) {return Ox.AMPM[Math.floor(Ox.getHours(d, utc) / 12)];}],
         ['Q', function(d) {return Math.floor(Ox.getMonth(d, utc) / 4) + 1;}],
         ['S', function(d) {return Ox.pad(Ox.getSeconds(d, utc), 2);}],
-        ['s', function(d) {return Math.floor(d.getTime() / 1000);}],
+        ['s', function(d) {
+            return Math.floor(d.getTime() / 1000)
+            - (utc ? Ox.getTimezoneOffset() / 1000 : 0);
+        }],
         ['U', function(d) {return Ox.pad(Ox.getWeek(d, utc), 2);}],
         ['u', function(d) {return Ox.getISODay(d, utc);}],
         ['V', function(d) {return Ox.pad(Ox.getISOWeek(d, utc), 2);}],