diff --git a/lib/src/base/accessor.dart b/lib/src/base/accessor.dart
index 0e60a20b..5ff86830 100644
--- a/lib/src/base/accessor.dart
+++ b/lib/src/base/accessor.dart
@@ -38,6 +38,7 @@ class Accessor extends GltfChildOfRootProperty {
   int _componentLength = -1;
   bool _isUnit = false;
   bool _isXyzSign = false;
+  bool _isCubicSpline = false;
   AccessorUsage _usage;
 
   Accessor._(
@@ -115,6 +116,7 @@ class Accessor extends GltfChildOfRootProperty {
 
   bool get isUnit => _isUnit;
   bool get isXyzSign => _isXyzSign;
+  bool get isCubicSpline => _isCubicSpline;
 
   AccessorUsage get usage => _usage;
 
@@ -339,6 +341,8 @@ class Accessor extends GltfChildOfRootProperty {
 
   void setXyzSign() => _isXyzSign = true;
 
+  void setCubicSpline() => _isCubicSpline = true;
+
   Iterable<num> getElements({bool normalize: false}) sync* {
     // Ensure required fields to not check for them each time
     if (componentType == -1 || count == -1 || type == null) {
@@ -533,7 +537,7 @@ class Accessor extends GltfChildOfRootProperty {
       return false;
     }
 
-    if (byteOffset % componentLength != 0) {
+    if (byteOffset.remainder(componentLength) != 0) {
       if (context != null) {
         context.addIssue(SemanticError.accessorOffsetAlignment,
             name: BYTE_OFFSET, args: [byteOffset, componentLength]);
@@ -548,7 +552,7 @@ class Accessor extends GltfChildOfRootProperty {
     }
 
     final totalOffset = bufferView.byteOffset + byteOffset;
-    if (totalOffset % componentLength != 0) {
+    if (totalOffset.remainder(componentLength) != 0) {
       if (context != null) {
         context.addIssue(LinkError.accessorTotalOffsetAlignment,
             name: BYTE_OFFSET, args: [totalOffset, componentLength]);
diff --git a/lib/src/base/animation.dart b/lib/src/base/animation.dart
index 55244405..b72f0ec2 100644
--- a/lib/src/base/animation.dart
+++ b/lib/src/base/animation.dart
@@ -196,6 +196,7 @@ class Animation extends GltfChildOfRootProperty {
 
                 if (channel._sampler.interpolation == CUBICSPLINE) {
                   outputCount *= 3;
+                  channel._sampler._output.setCubicSpline();
                 }
 
                 if (channel.target.path == WEIGHTS) {
diff --git a/lib/src/base/buffer_view.dart b/lib/src/base/buffer_view.dart
index 8a68e39b..58db0405 100644
--- a/lib/src/base/buffer_view.dart
+++ b/lib/src/base/buffer_view.dart
@@ -93,7 +93,7 @@ class BufferView extends GltfChildOfRootProperty {
             name: BYTE_STRIDE, args: [byteStride, byteLength]);
       }
 
-      if (byteStride % 4 != 0) {
+      if (byteStride.remainder(4) != 0) {
         context.addIssue(SchemaError.valueMultipleOf,
             name: BYTE_STRIDE, args: [byteStride, 4]);
       }
diff --git a/lib/src/base/mesh.dart b/lib/src/base/mesh.dart
index 3d2c9b74..1d18b16b 100644
--- a/lib/src/base/mesh.dart
+++ b/lib/src/base/mesh.dart
@@ -321,8 +321,9 @@ class MeshPrimitive extends GltfProperty {
                   args: [format, validFormats]);
             }
 
-            if ((accessor.byteOffset != -1 && accessor.byteOffset % 4 != 0) ||
-                (accessor.elementLength % 4 != 0 &&
+            if ((accessor.byteOffset != -1 &&
+                    accessor.byteOffset.remainder(4) != 0) ||
+                (accessor.elementLength.remainder(4) != 0 &&
                     accessor.bufferView != null &&
                     accessor.bufferView.byteStride == -1)) {
               context.addIssue(LinkError.meshPrimitiveAccessorUnaligned,
@@ -396,9 +397,9 @@ class MeshPrimitive extends GltfProperty {
     */
 
     if ((context.validate && _count != -1) &&
-        ((mode == 1 && _count % 2 != 0) ||
+        ((mode == 1 && _count.remainder(2) != 0) ||
             ((mode == 2 || mode == 3) && _count < 2) ||
-            (mode == 4 && _count % 3 != 0) ||
+            (mode == 4 && _count.remainder(3) != 0) ||
             ((mode == 5 || mode == 6) && _count < 3))) {
       context.addIssue(LinkError.meshPrimitiveIncompatibleMode,
           args: [_count, gl.MODES_NAMES[mode]]);
@@ -467,8 +468,9 @@ class MeshPrimitive extends GltfProperty {
                     args: [format, validFormats]);
               }
 
-              if ((accessor.byteOffset != -1 && accessor.byteOffset % 4 != 0) ||
-                  (accessor.elementLength % 4 != 0 &&
+              if ((accessor.byteOffset != -1 &&
+                      accessor.byteOffset.remainder(4) != 0) ||
+                  (accessor.elementLength.remainder(4) != 0 &&
                       accessor.bufferView != null &&
                       accessor.bufferView.byteStride == -1)) {
                 context.addIssue(LinkError.meshPrimitiveAccessorUnaligned,
diff --git a/lib/src/data_access/validate_accessors.dart b/lib/src/data_access/validate_accessors.dart
index 008578db..be793769 100644
--- a/lib/src/data_access/validate_accessors.dart
+++ b/lib/src/data_access/validate_accessors.dart
@@ -75,6 +75,10 @@ void validateAccessorsData(Gltf gltf, Context context) {
       return;
     }
 
+    if (accessor.isCubicSpline && accessor.count.remainder(3) != 0) {
+      return;
+    }
+
     // Skip empty accessors
     if (accessor.bufferView == null && accessor.sparse == null) {
       return;
@@ -109,6 +113,9 @@ void validateAccessorsData(Gltf gltf, Context context) {
     var index = 0;
     var componentIndex = 0;
 
+    // 0: in; 1: value; 2: out
+    var cubicSplineState = 0;
+
     final iterator = gltf.accessors[i].getElements().iterator;
 
     var hasNext = iterator.moveNext();
@@ -184,7 +191,8 @@ void validateAccessorsData(Gltf gltf, Context context) {
           } else if (accessor.usage == AccessorUsage.IBM) {
             matrix.storage[componentIndex] = value;
           } else if (accessor.isUnit &&
-              !(accessor.isXyzSign && componentIndex == 3)) {
+              !(accessor.isXyzSign && componentIndex == 3) &&
+              !(accessor.isCubicSpline && cubicSplineState != 1)) {
             sum += value * value;
           }
         }
@@ -194,7 +202,8 @@ void validateAccessorsData(Gltf gltf, Context context) {
             if (!isTrsDecomposable(matrix)) {
               context.addIssue(DataError.indecomposableMatrix, args: [index]);
             }
-          } else if (accessor.isUnit) {
+          } else if (accessor.isUnit &&
+              !(accessor.isCubicSpline && cubicSplineState != 1)) {
             if ((sum - 1.0).abs() > 0.0005) {
               context.addIssue(DataError.accessorNonUnit,
                   args: [index, sqrt(sum)]);
@@ -207,6 +216,10 @@ void validateAccessorsData(Gltf gltf, Context context) {
             }
           }
 
+          if (accessor.isCubicSpline && ++cubicSplineState == 3) {
+            cubicSplineState = 0;
+          }
+
           componentIndex = 0;
         }