diff --git a/src/tests/end2end/CopyTests.cpp b/src/tests/end2end/CopyTests.cpp
index 8194cb4cd7..0a5076d5f5 100644
--- a/src/tests/end2end/CopyTests.cpp
+++ b/src/tests/end2end/CopyTests.cpp
@@ -151,8 +151,8 @@ class CopyTests_T2B : public CopyTests {
         // Layout for initial data upload to texture.
         // Some parts of this result are also reused later.
         const utils::TextureDataCopyLayout copyLayout =
-            utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
-                textureSpec.format, textureSpec.textureSize, textureSpec.copyLevel);
+            utils::GetTextureDataCopyLayoutForTextureAtLevel(
+                textureSpec.format, textureSpec.textureSize, textureSpec.copyLevel, dimension);
 
         // Initialize the source texture
         std::vector<RGBA8> textureArrayData = GetExpectedTextureDataRGBA8(copyLayout);
@@ -279,8 +279,8 @@ class CopyTests_B2T : public CopyTests {
         queue.Submit(1, &commands);
 
         const utils::TextureDataCopyLayout copyLayout =
-            utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
-                textureSpec.format, textureSpec.textureSize, textureSpec.copyLevel,
+            utils::GetTextureDataCopyLayoutForTextureAtLevel(
+                textureSpec.format, textureSpec.textureSize, textureSpec.copyLevel, dimension,
                 bufferSpec.rowsPerImage);
 
         uint32_t copyLayer = copySize.depthOrArrayLayers;
@@ -367,11 +367,11 @@ class CopyTests_T2T : public CopyTests {
         // Create an upload buffer and use it to populate the current slice of the texture in
         // `level` mip level
         const utils::TextureDataCopyLayout srcDataCopyLayout =
-            utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
+            utils::GetTextureDataCopyLayoutForTextureAtLevel(
                 format,
                 {srcSpec.textureSize.width, srcSpec.textureSize.height,
                  copySize.depthOrArrayLayers},
-                srcSpec.copyLevel);
+                srcSpec.copyLevel, srcDimension);
 
         // Initialize the source texture
         const std::vector<uint8_t> srcTextureCopyData = GetExpectedTextureData(srcDataCopyLayout);
@@ -397,11 +397,11 @@ class CopyTests_T2T : public CopyTests {
         // Copy the data from the srcSpec.copyOrigin.z-th layer to (srcSpec.copyOrigin.z +
         // copySize.depthOrArrayLayers)-th layer of dstTexture to outputBuffer
         const utils::TextureDataCopyLayout dstDataCopyLayout =
-            utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
+            utils::GetTextureDataCopyLayoutForTextureAtLevel(
                 format,
                 {dstSpec.textureSize.width, dstSpec.textureSize.height,
                  copySize.depthOrArrayLayers},
-                dstSpec.copyLevel);
+                dstSpec.copyLevel, dstDimension);
         wgpu::BufferDescriptor outputBufferDescriptor;
         outputBufferDescriptor.size = dstDataCopyLayout.byteLength;
         outputBufferDescriptor.usage = wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::CopyDst;
@@ -1161,6 +1161,44 @@ TEST_P(CopyTests_T2B, Texture3DCopyHeightIsOneCopyWidthIsSmall) {
     DoTest(textureSpec, bufferSpec, {kWidth, kHeight, kDepth}, wgpu::TextureDimension::e3D);
 }
 
+// Test that copying texture 3D array mips with 256-byte aligned sizes works
+TEST_P(CopyTests_T2B, Texture3DMipAligned) {
+    constexpr uint32_t kWidth = 256;
+    constexpr uint32_t kHeight = 128;
+    constexpr uint32_t kDepth = 64u;
+
+    TextureSpec defaultTextureSpec;
+    defaultTextureSpec.textureSize = {kWidth, kHeight, kDepth};
+
+    for (unsigned int i = 1; i < 6; ++i) {
+        TextureSpec textureSpec = defaultTextureSpec;
+        textureSpec.copyLevel = i;
+        textureSpec.levelCount = i + 1;
+
+        DoTest(textureSpec, MinimumBufferSpec(kWidth >> i, kHeight >> i, kDepth >> i),
+               {kWidth >> i, kHeight >> i, kDepth >> i}, wgpu::TextureDimension::e3D);
+    }
+}
+
+// Test that copying texture 3D array mips with 256-byte unaligned sizes works
+TEST_P(CopyTests_T2B, Texture3DMipUnaligned) {
+    constexpr uint32_t kWidth = 261;
+    constexpr uint32_t kHeight = 123;
+    constexpr uint32_t kDepth = 69u;
+
+    TextureSpec defaultTextureSpec;
+    defaultTextureSpec.textureSize = {kWidth, kHeight, kDepth};
+
+    for (unsigned int i = 1; i < 6; ++i) {
+        TextureSpec textureSpec = defaultTextureSpec;
+        textureSpec.copyLevel = i;
+        textureSpec.levelCount = i + 1;
+
+        DoTest(textureSpec, MinimumBufferSpec(kWidth >> i, kHeight >> i, kDepth >> i),
+               {kWidth >> i, kHeight >> i, kDepth >> i}, wgpu::TextureDimension::e3D);
+    }
+}
+
 // TODO(yunchao.he@intel.com): add T2B tests for 3D textures, like RowPitch,
 // RowsPerImage, buffer offset, partial depth range, non-zero level, etc.
 
@@ -1740,6 +1778,44 @@ TEST_P(CopyTests_B2T, Texture3DCopyHeightIsOneCopyWidthIsSmall) {
     DoTest(textureSpec, bufferSpec, {kWidth, kHeight, kDepth}, wgpu::TextureDimension::e3D);
 }
 
+// Test that copying texture 3D array mips with 256-byte aligned sizes works
+TEST_P(CopyTests_B2T, Texture3DMipAligned) {
+    constexpr uint32_t kWidth = 256;
+    constexpr uint32_t kHeight = 128;
+    constexpr uint32_t kDepth = 64u;
+
+    TextureSpec defaultTextureSpec;
+    defaultTextureSpec.textureSize = {kWidth, kHeight, kDepth};
+
+    for (unsigned int i = 1; i < 6; ++i) {
+        TextureSpec textureSpec = defaultTextureSpec;
+        textureSpec.copyLevel = i;
+        textureSpec.levelCount = i + 1;
+
+        DoTest(textureSpec, MinimumBufferSpec(kWidth >> i, kHeight >> i, kDepth >> i),
+               {kWidth >> i, kHeight >> i, kDepth >> i}, wgpu::TextureDimension::e3D);
+    }
+}
+
+// Test that copying texture 3D array mips with 256-byte unaligned sizes works
+TEST_P(CopyTests_B2T, Texture3DMipUnaligned) {
+    constexpr uint32_t kWidth = 261;
+    constexpr uint32_t kHeight = 123;
+    constexpr uint32_t kDepth = 69u;
+
+    TextureSpec defaultTextureSpec;
+    defaultTextureSpec.textureSize = {kWidth, kHeight, kDepth};
+
+    for (unsigned int i = 1; i < 6; ++i) {
+        TextureSpec textureSpec = defaultTextureSpec;
+        textureSpec.copyLevel = i;
+        textureSpec.levelCount = i + 1;
+
+        DoTest(textureSpec, MinimumBufferSpec(kWidth >> i, kHeight >> i, kDepth >> i),
+               {kWidth >> i, kHeight >> i, kDepth >> i}, wgpu::TextureDimension::e3D);
+    }
+}
+
 // TODO(yunchao.he@intel.com): add more tests like RowPitch, RowsPerImage, buffer offset, partial
 // depth range, non-zero level, etc.
 
diff --git a/src/tests/end2end/CopyTextureForBrowserTests.cpp b/src/tests/end2end/CopyTextureForBrowserTests.cpp
index 1cce29a455..5bd197c51f 100644
--- a/src/tests/end2end/CopyTextureForBrowserTests.cpp
+++ b/src/tests/end2end/CopyTextureForBrowserTests.cpp
@@ -247,7 +247,7 @@ class CopyTextureForBrowserTests : public DawnTest {
         wgpu::Texture srcTexture = device.CreateTexture(&srcDescriptor);
 
         const utils::TextureDataCopyLayout srcCopyLayout =
-            utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
+            utils::GetTextureDataCopyLayoutForTextureAtLevel(
                 kTextureFormat,
                 {srcSpec.textureSize.width, srcSpec.textureSize.height,
                  copySize.depthOrArrayLayers},
@@ -293,7 +293,7 @@ class CopyTextureForBrowserTests : public DawnTest {
         if (testSubRectCopy) {
             // For subrect copy tests, dst texture use kTextureFormat always.
             const utils::TextureDataCopyLayout dstCopyLayout =
-                utils::GetTextureDataCopyLayoutForTexture2DAtLevel(
+                utils::GetTextureDataCopyLayoutForTextureAtLevel(
                     kTextureFormat,
                     {dstSpec.textureSize.width, dstSpec.textureSize.height,
                      copySize.depthOrArrayLayers},
diff --git a/src/utils/TestUtils.cpp b/src/utils/TestUtils.cpp
index cac3a1ac9c..433ef3730f 100644
--- a/src/utils/TestUtils.cpp
+++ b/src/utils/TestUtils.cpp
@@ -31,10 +31,11 @@ namespace utils {
         return Align(bytesPerBlock * (width / blockWidth), kTextureBytesPerRowAlignment);
     }
 
-    TextureDataCopyLayout GetTextureDataCopyLayoutForTexture2DAtLevel(
+    TextureDataCopyLayout GetTextureDataCopyLayoutForTextureAtLevel(
         wgpu::TextureFormat format,
         wgpu::Extent3D textureSizeAtLevel0,
         uint32_t mipmapLevel,
+        wgpu::TextureDimension dimension,
         uint32_t rowsPerImage) {
         // Compressed texture formats not supported in this function yet.
         ASSERT(utils::GetTextureFormatBlockWidth(format) == 1);
@@ -45,6 +46,11 @@ namespace utils {
                           std::max(textureSizeAtLevel0.height >> mipmapLevel, 1u),
                           textureSizeAtLevel0.depthOrArrayLayers};
 
+        if (dimension == wgpu::TextureDimension::e3D) {
+            layout.mipSize.depthOrArrayLayers =
+                std::max(textureSizeAtLevel0.depthOrArrayLayers >> mipmapLevel, 1u);
+        }
+
         layout.bytesPerRow = GetMinimumBytesPerRow(format, layout.mipSize.width);
 
         if (rowsPerImage == wgpu::kCopyStrideUndefined) {
diff --git a/src/utils/TestUtils.h b/src/utils/TestUtils.h
index 013de67d80..d611124175 100644
--- a/src/utils/TestUtils.h
+++ b/src/utils/TestUtils.h
@@ -31,10 +31,11 @@ namespace utils {
     };
 
     uint32_t GetMinimumBytesPerRow(wgpu::TextureFormat format, uint32_t width);
-    TextureDataCopyLayout GetTextureDataCopyLayoutForTexture2DAtLevel(
+    TextureDataCopyLayout GetTextureDataCopyLayoutForTextureAtLevel(
         wgpu::TextureFormat format,
         wgpu::Extent3D textureSizeAtLevel0,
         uint32_t mipmapLevel,
+        wgpu::TextureDimension dimension = wgpu::TextureDimension::e2D,
         uint32_t rowsPerImage = wgpu::kCopyStrideUndefined);
 
     uint64_t RequiredBytesInCopy(uint64_t bytesPerRow,