diff --git a/components/style/properties/longhand/inherited_svg.mako.rs b/components/style/properties/longhand/inherited_svg.mako.rs
index 7ac8feb2d1a..98112efbba0 100644
--- a/components/style/properties/longhand/inherited_svg.mako.rs
+++ b/components/style/properties/longhand/inherited_svg.mako.rs
@@ -65,6 +65,16 @@ ${helpers.predefined_type(
     boxed=True,
     spec="https://www.w3.org/TR/SVG2/painting.html#SpecifyingStrokePaint")}
 
+${helpers.predefined_type(
+    "stroke-width", "LengthOrPercentage",
+    "computed::LengthOrPercentage::one()",
+    "parse_non_negative",
+    products="gecko",
+    animatable=True,
+    needs_context=False,
+    boxed=True,
+    spec="https://www.w3.org/TR/SVG2/painting.html#StrokeWidth")}
+
 ${helpers.single_keyword("stroke-linecap", "butt round square",
                          products="gecko", animatable=False,
                          spec="https://www.w3.org/TR/SVG11/painting.html#StrokeLinecapProperty")}
diff --git a/components/style/values/computed/length.rs b/components/style/values/computed/length.rs
index 74c9fd6287f..492bbfb4bc0 100644
--- a/components/style/values/computed/length.rs
+++ b/components/style/values/computed/length.rs
@@ -4,7 +4,7 @@
 
 //! `<length>` computed values, and related ones.
 
-use app_units::Au;
+use app_units::{Au, AU_PER_PX};
 use ordered_float::NotNaN;
 use std::fmt;
 use style_traits::ToCss;
@@ -195,6 +195,12 @@ impl LengthOrPercentage {
         LengthOrPercentage::Length(Au(0))
     }
 
+    #[inline]
+    /// 1px length value for SVG defaults
+    pub fn one() -> LengthOrPercentage {
+        LengthOrPercentage::Length(Au(AU_PER_PX))
+    }
+
     /// Returns true if the computed value is absolute 0 or 0%.
     ///
     /// (Returns false for calc() values, even if ones that may resolve to zero.)