diff --git a/src/builtin/string.rs b/src/builtin/string.rs
index a7dac57..5b0bf16 100644
--- a/src/builtin/string.rs
+++ b/src/builtin/string.rs
@@ -57,6 +57,7 @@ pub(crate) fn register(f: &mut BTreeMap<String, Builtin>) {
         };
         let mut end = match arg!(args, 2, "end-at"=Value::Null).eval() {
             Value::Dimension(n, Unit::None) if n.to_integer().is_positive() => n.to_integer().to_usize().unwrap(),
+            Value::Dimension(n, Unit::None) if n == Number::from(0) => 0_usize,
             Value::Dimension(n, Unit::None) if n < -Number::from(str_len) => 0_usize,
             Value::Dimension(n, Unit::None) => (BigInt::from(str_len + 1) + n.to_integer()).to_usize().unwrap(),
             Value::Dimension(..) => todo!("$end: Expected ___ to have no units."),
diff --git a/tests/strings.rs b/tests/strings.rs
index 8f955d9..6be6930 100644
--- a/tests/strings.rs
+++ b/tests/strings.rs
@@ -78,3 +78,8 @@ test!(
     "a {\n  color: str-slice(\"cde\", 0, -100);\n}\n",
     "a {\n  color: \"\";\n}\n"
 );
+test!(
+    str_slice_end_0,
+    "a {\n  color: str-slice(\"cde\", 1, 0);\n}\n",
+    "a {\n  color: \"\";\n}\n"
+);