diff --git a/less/_03-grids.less b/less/_03-grids.less
index 4197e04..f898908 100644
--- a/less/_03-grids.less
+++ b/less/_03-grids.less
@@ -27,7 +27,7 @@
 [class*="@{kna-namespace}grid-"] > * {
 	flex: 0 0 auto;
 	display: block; /* IE fix */
-	width: ~'calc(100% * 1 / @{number} - @{gutter})';
+	width: ~'calc(100% * 1 / @{number} - @{gutter} - .01px)';
 	margin-left: @gutter;
 }
 
@@ -35,25 +35,25 @@
 // example : .grid-perso { .grid(12); }
 .grid(@number:@number, @gutter:@gutter) {
  & > * {
-	  width: ~'calc(100% * 1 / @{number} - @{gutter})';
+	  width: ~'calc(100% * 1 / @{number} - @{gutter} - .01px)';
 	}
 	& > .@{kna-namespace}flex-item-double {
-		width: ~'calc(100% * 2 / @{number} - @{gutter})';
+		width: ~'calc(100% * 2 / @{number} - @{gutter} - .01px)';
 	}
 	@media (min-width: (@tiny-screen + 1)) and (max-width: @small-screen) {
 		& > * {
-			width: ~'calc(100% * 1 / 2 - @{gutter})';
+			width: ~'calc(100% * 1 / 2 - @{gutter} - .01px)';
 		}
 		& > .@{kna-namespace}flex-item-double {
-			width: ~'calc(100% - @{gutter})';
+			width: ~'calc(100% - @{gutter} - .01px)';
 		}
 	}
 	@media (max-width: @tiny-screen) {
 		& > * {
-			width: ~'calc(100% - @{gutter})';
+			width: ~'calc(100% - @{gutter} - .01px)';
 		}
 		& > .@{kna-namespace}flex-item-double {
-			width: ~'calc(100% - @{gutter})';
+			width: ~'calc(100% - @{gutter} - .01px)';
 		}
 	}
 }
diff --git a/sass/_03-grids.scss b/sass/_03-grids.scss
index 64b17df..8db3eb4 100644
--- a/sass/_03-grids.scss
+++ b/sass/_03-grids.scss
@@ -27,7 +27,7 @@
 [class*="#{$kna-namespace}grid-"] > * {
 	flex: 0 0 auto;
 	display: block; /* IE fix */
-	width: calc(100% * 1 / #{$number} - #{$gutter});
+	width: calc(100% * 1 / #{$number} - #{$gutter} - .01px);
 	margin-left: $gutter;
 }
 
@@ -35,25 +35,25 @@
 // example : .grid-perso { @include grid(12); }
 @mixin grid($number:$number,$gutter:$gutter) {
 & > * {
-	width: calc(100% * 1 / #{$number} - #{$gutter});
+	width: calc(100% * 1 / #{$number} - #{$gutter} - .01px);
 }
 & > .#{$kna-namespace}flex-item-double {
 	width: calc(100% * 2 / #{$number} - #{$gutter});
 }
 	@media (min-width: ($tiny-screen + 1)) and (max-width: $small-screen) {
 		& > * {
-			width: calc(100% * 1 / 2 - #{$gutter});
+			width: calc(100% * 1 / 2 - #{$gutter} - .01px);
 		}
 		& > .#{$kna-namespace}flex-item-double {
-			width: calc(100% - #{$gutter});
+			width: calc(100% - #{$gutter} - .01px);
 		}
 	}
 	@media (max-width: $tiny-screen) {
 		& > * {
-			width: calc(100% - #{$gutter});
+			width: calc(100% - #{$gutter} - .01px);
 		}
 		& > .#{$kna-namespace}flex-item-double {
-			width: calc(100% - #{$gutter});
+			width: calc(100% - #{$gutter} - .01px);
 		}
 	}
 }