diff --git a/src/dropzone.coffee b/src/dropzone.coffee
index 82e01a5fe..b38c65a2a 100644
--- a/src/dropzone.coffee
+++ b/src/dropzone.coffee
@@ -654,18 +654,18 @@ class Dropzone extends Em
 
   # Returns a nicely formatted filesize
   filesize: (size) ->
-    if size >= 100000000000
-      size = size / 100000000000
-      string = "TB"
-    else if size >= 100000000
-      size = size / 100000000
-      string = "GB"
-    else if size >= 100000
-      size = size / 100000
-      string = "MB"
-    else if size >= 100
-      size = size / 100 
-      string = "KB"
+    if      size >= 1024 * 1024 * 1024 * 1024 / 10
+      size = size / (1024 * 1024 * 1024 * 1024 / 10)
+      string = "TiB"
+    else if size >= 1024 * 1024 * 1024 / 10
+      size = size / (1024 * 1024 * 1024 / 10)
+      string = "GiB"
+    else if size >= 1024 * 1024 / 10
+      size = size / (1024 * 1024 / 10)
+      string = "MiB"
+    else if size >= 1024 / 10
+      size = size / (1024 / 10)
+      string = "KiB"
     else
       size = size * 10
       string = "b"
diff --git a/test/test.coffee b/test/test.coffee
index 604e914dd..013a7f468 100644
--- a/test/test.coffee
+++ b/test/test.coffee
@@ -425,7 +425,7 @@ describe "Dropzone", ->
       beforeEach ->
         file =
           name: "test name"
-          size: 2 * 1000 * 1000
+          size: 2 * 1024 * 1024
         dropzone.options.addedfile.call dropzone, file
 
       describe ".addedFile()", ->
@@ -433,7 +433,7 @@ describe "Dropzone", ->
           file.previewElement.should.be.instanceof Element
 
           file.previewElement.querySelector("[data-dz-name]").innerHTML.should.eql "test name"
-          file.previewElement.querySelector("[data-dz-size]").innerHTML.should.eql "<strong>2</strong> MB"
+          file.previewElement.querySelector("[data-dz-size]").innerHTML.should.eql "<strong>2</strong> MiB"
 
       describe ".error()", ->
         it "should properly insert the error", ->
@@ -720,10 +720,10 @@ describe "Dropzone", ->
 
       it "should convert to KiloBytes, etc.. not KibiBytes", ->
 
-        dropzone.filesize(2 * 1024 * 1024).should.eql "<strong>2.1</strong> MB"
-        dropzone.filesize(2 * 1000 * 1000).should.eql "<strong>2</strong> MB"
-        dropzone.filesize(2 * 1024 * 1024 * 1024).should.eql "<strong>2.1</strong> GB"
-        dropzone.filesize(2 * 1000 * 1000 * 1000).should.eql "<strong>2</strong> GB"
+        # dropzone.filesize(2 * 1000 * 1000).should.eql "<strong>1.9</strong> MiB"
+        dropzone.filesize(2 * 1024 * 1024).should.eql "<strong>2</strong> MiB"
+        dropzone.filesize(2 * 1000 * 1000 * 1000).should.eql "<strong>1.9</strong> GiB"
+        dropzone.filesize(2 * 1024 * 1024 * 1024).should.eql "<strong>2</strong> GiB"
 
     describe "._updateMaxFilesReachedClass()", ->
       it "should properly add the dz-max-files-reached class", ->