diff --git a/API.md b/API.md
index edb933d6..f4220556 100644
--- a/API.md
+++ b/API.md
@@ -1696,7 +1696,7 @@ A data source from an image can be one of the following types:
 | `data`             | Input data (see below)                                                                                                                                           |             |
 | `mipmap`           | See below for a description                                                                                                                                      | `false`     |
 | `flipY`            | Flips textures vertically when uploading                                                                                                                         | `false`     |
-| `alignment`        | Sets unpack alignment per pixel                                                                                                                                  | `1`         |
+| `alignment`        | Sets unpack alignment per row                                                                                                                                  | `1`         |
 | `premultiplyAlpha` | Premultiply alpha when unpacking                                                                                                                                 | `false`     |
 | `colorSpace`       | Sets colorspace conversion                                                                                                                                       | `'none'`    |
 | `data`             | Image data for the texture                                                                                                                                       | `null`      |
diff --git a/README.md b/README.md
index 6a1d2b3e..cc8231c6 100644
--- a/README.md
+++ b/README.md
@@ -72,7 +72,7 @@
 
 To define a command you specify a mixture of static and dynamic data for the object. Once this is done, `regl` takes this description and then compiles it into optimized JavaScript code.  For example, here is a simple `regl` program to draw a triangle:
 
-```JavaScript
+```js
 // Calling the regl module with no arguments creates a full screen canvas and
 // WebGL context, and then uses this context to initialize a new REGL instance
 const regl = require('regl')()
diff --git a/lib/util/check.js b/lib/util/check.js
index b79fed39..d7298d77 100644
--- a/lib/util/check.js
+++ b/lib/util/check.js
@@ -530,8 +530,10 @@ function checkTexture2D (info, mipData, limits) {
       if (img.compressed) {
         // TODO: check size for compressed images
       } else if (img.data) {
-        check(img.data.byteLength === mw * mh *
-          Math.max(pixelSize(img.type, c), img.unpackAlignment),
+        // check(img.data.byteLength === mw * mh *
+        // Math.max(pixelSize(img.type, c), img.unpackAlignment),
+        var rowSize = Math.ceil(pixelSize(img.type, c) * mw / img.unpackAlignment) * img.unpackAlignment
+        check(img.data.byteLength === rowSize * mh,
           'invalid data for image, buffer size is inconsistent with image format')
       } else if (img.element) {
         // TODO: check element can be loaded
diff --git a/test/texture2d.js b/test/texture2d.js
index 184a561a..0541594f 100644
--- a/test/texture2d.js
+++ b/test/texture2d.js
@@ -515,9 +515,9 @@ tape('texture 2d', function (t) {
     regl.texture({
       shape: [2, 2, 1],
       flipY: true,
-      alignment: 2,
+      alignment: 4,
       colorSpace: 'none',
-      data: new Uint8Array([1, 0, 2, 0, 3, 0, 4, 0])
+      data: new Uint8Array([1, 2, 0, 0, 3, 4, 0, 0])
     }),
     {
       width: 2,
@@ -535,7 +535,7 @@ tape('texture 2d', function (t) {
     regl.texture({
       shape: [4, 4, 1],
       flipY: true,
-      alignment: 2,
+      alignment: 4,
       mipmap: [
         {
           alignment: 1,
@@ -549,7 +549,7 @@ tape('texture 2d', function (t) {
         {
           flipY: false,
           colorSpace: 'none',
-          data: new Uint8Array([1, 0, 2, 0, 3, 0, 4, 0])
+          data: new Uint8Array([1, 2, 0, 0, 3, 4, 0, 0])
         },
         {
           alignment: 1,