diff --git a/font/src/darwin/mod.rs b/font/src/darwin/mod.rs
index 757dd5f8..9e92923e 100644
--- a/font/src/darwin/mod.rs
+++ b/font/src/darwin/mod.rs
@@ -135,9 +135,7 @@ impl ::Rasterize for Rasterizer {
     }
 
     /// Get metrics for font specified by FontKey
-    fn metrics(&self, key: FontKey, _size: Size) -> Result<Metrics, Error> {
-        // NOTE size is not needed here since the font loaded already contains
-        // it. It's part of the API due to platform differences.
+    fn metrics(&self, key: FontKey) -> Result<Metrics, Error> {
         let font = self.fonts
             .get(&key)
             .ok_or(Error::FontNotLoaded)?;
diff --git a/font/src/ft/mod.rs b/font/src/ft/mod.rs
index 24ef5c77..c04057cd 100644
--- a/font/src/ft/mod.rs
+++ b/font/src/ft/mod.rs
@@ -54,7 +54,7 @@ impl ::Rasterize for FreeTypeRasterizer {
         })
     }
 
-    fn metrics(&self, key: FontKey, size: Size) -> Result<Metrics, Error> {
+    fn metrics(&self, key: FontKey) -> Result<Metrics, Error> {
         let face = self.faces
             .get(&key)
             .ok_or(Error::FontNotLoaded)?;
diff --git a/font/src/lib.rs b/font/src/lib.rs
index 7b8d92e7..292e2244 100644
--- a/font/src/lib.rs
+++ b/font/src/lib.rs
@@ -229,8 +229,8 @@ pub trait Rasterize {
     fn new(dpi_x: f32, dpi_y: f32, device_pixel_ratio: f32, use_thin_strokes: bool) -> Result<Self, Self::Err>
         where Self: Sized;
 
-    /// Get `Metrics` for the given `FontKey` and `Size`
-    fn metrics(&self, FontKey, Size) -> Result<Metrics, Self::Err>;
+    /// Get `Metrics` for the given `FontKey`
+    fn metrics(&self, FontKey) -> Result<Metrics, Self::Err>;
 
     /// Load the font described by `FontDesc` and `Size`
     fn load_font(&mut self, &FontDesc, Size) -> Result<FontKey, Self::Err>;
diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs
index 585bea10..13e84807 100644
--- a/src/renderer/mod.rs
+++ b/src/renderer/mod.rs
@@ -246,7 +246,7 @@ impl GlyphCache {
 
     pub fn font_metrics(&self) -> font::Metrics {
         self.rasterizer
-            .metrics(self.font_key, self.font_size)
+            .metrics(self.font_key)
             .expect("metrics load since font is loaded at glyph cache creation")
     }