diff --git a/src/uu/dd/src/dd.rs b/src/uu/dd/src/dd.rs
index e6698244b..51f82c0f6 100644
--- a/src/uu/dd/src/dd.rs
+++ b/src/uu/dd/src/dd.rs
@@ -118,6 +118,18 @@ impl<R: Read> Read for Input<R>
             }
         }
 
+        if self.cf.swab
+        {
+            let mut tmp = DEFAULT_FILL_BYTE;
+
+            for base in (1..len).step_by(2)
+            {
+                tmp = buf[base];
+                buf[base] = buf[base-1];
+                buf[base-1] = tmp;
+            }
+        }
+
         Ok(len)
     }
 }
diff --git a/src/uu/dd/src/dd_test.rs b/src/uu/dd/src/dd_test.rs
index c2167a5e6..d73a9ede2 100644
--- a/src/uu/dd/src/dd_test.rs
+++ b/src/uu/dd/src/dd_test.rs
@@ -41,35 +41,35 @@ macro_rules! make_spec_test (
     ( $test_id:ident, $test_name:expr, $src:expr ) =>
     {
         // When spec not given, output should match input
-        make_spec_test!($test_id, $test_name, $src, None, $src);
+        make_spec_test!($test_id, $test_name, $src, $src);
     };
     ( $test_id:ident, $test_name:expr, $src:expr, $spec:expr ) =>
     {
-        make_spec_test!($test_id, $test_name, $src, None, $spec);
+        make_spec_test!($test_id,
+                        $test_name,
+                        Input {
+                            src: $src,
+                            ibs: 512,
+                            xfer_stats: StatusLevel::None,
+                            cf: cfi!(),
+                        },
+                        Output {
+                            dst: File::create(format!("./test-resources/FAILED-{}.test", $test_name)).unwrap(),
+                            obs: 512,
+                            cf: DEFAULT_CFO,
+                        },
+                        $spec,
+                        format!("./test-resources/FAILED-{}.test", $test_name)
+        );
     };
-    ( $test_id:ident, $test_name:expr, $src:expr, $ctable:expr, $spec:expr ) =>
+    ( $test_id:ident, $test_name:expr, $i:expr, $o:expr, $spec:expr, $tmp_fname:expr ) =>
     {
         #[test]
         fn $test_id()
         {
-            let tmp_fname = format!("./test-resources/FAILED-{}.test", $test_name);
+            dd($i,$o).unwrap();
 
-            let i = Input {
-                src: $src,
-                ibs: 512,
-                xfer_stats: StatusLevel::None,
-                cf: cfi!($ctable),
-            };
-
-            let o = Output {
-                dst: File::create(&tmp_fname).unwrap(),
-                obs: 512,
-                cf: DEFAULT_CFO,
-            };
-
-            dd(i,o).unwrap();
-
-            let res = File::open(&tmp_fname).unwrap();
+            let res = File::open($tmp_fname).unwrap();
             let res = BufReader::new(res);
 
             let spec = BufReader::new($spec);
@@ -80,34 +80,56 @@ macro_rules! make_spec_test (
                            b_spec.unwrap());
             }
 
-            fs::remove_file(&tmp_fname).unwrap();
+            fs::remove_file($tmp_fname).unwrap();
         }
     };
 );
 
-#[test]
-fn test_input_parser()
-{
-    let args = vec![
-        String::from("ketchup"),
-        String::from("mustard"),
-        String::from("--conv=ibm"),
-        String::from("relish"),
-    ];
+macro_rules! make_conv_test (
+    ( $test_id:ident, $test_name:expr, $src:expr, $ctable:expr, $spec:expr ) =>
+    {
+        make_spec_test!($test_id,
+                        $test_name,
+                        Input {
+                            src: $src,
+                            ibs: 512,
+                            xfer_stats: StatusLevel::None,
+                            cf: cfi!($ctable),
+                        },
+                        Output {
+                            dst: File::create(format!("./test-resources/FAILED-{}.test", $test_name)).unwrap(),
+                            obs: 512,
+                            cf: DEFAULT_CFO,
+                        },
+                        $spec,
+                        format!("./test-resources/FAILED-{}.test", $test_name)
+        );
+    };
+);
 
-    let matches = build_app!().parse(args);
-    // ...
+macro_rules! make_cfi_test (
+    ( $test_id:ident, $test_name:expr, $src:expr, $cfi:expr, $spec:expr ) =>
+    {
+        make_spec_test!($test_id,
+                        $test_name,
+                        Input {
+                            src: $src,
+                            ibs: 512,
+                            xfer_stats: StatusLevel::None,
+                            cf: $cfi,
+                        },
+                        Output {
+                            dst: File::create(format!("./test-resources/FAILED-{}.test", $test_name)).unwrap(),
+                            obs: 512,
+                            cf: DEFAULT_CFO,
+                        },
+                        $spec,
+                        format!("./test-resources/FAILED-{}.test", $test_name)
+        );
+    };
+);
 
-    unimplemented!()
-}
-
-#[test]
-fn test_output_parser()
-{
-    unimplemented!()
-}
-
-  make_spec_test!(
+make_spec_test!(
     zeros_4k_test,
     "zeros-4k",
     File::open("./test-resources/zeros-620f0b67a91f7f74151bc5be745b7110.test").unwrap()
@@ -131,7 +153,7 @@ make_spec_test!(
     File::open("./test-resources/random-5828891cb1230748e146f34223bbd3b5.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     atoe_conv_spec_test,
     "atoe-conv-spec-test",
     File::open("./test-resources/seq-byte-values-b632a992d3aed5d8d1a59cc5a5a455ba.test").unwrap(),
@@ -139,7 +161,7 @@ make_spec_test!(
     File::open("./test-resources/gnudd-conv-atoe-seq-byte-values.spec").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     etoa_conv_spec_test,
     "etoa-conv-spec-test",
     File::open("./test-resources/seq-byte-values-b632a992d3aed5d8d1a59cc5a5a455ba.test").unwrap(),
@@ -147,7 +169,7 @@ make_spec_test!(
     File::open("./test-resources/gnudd-conv-etoa-seq-byte-values.spec").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     atoibm_conv_spec_test,
     "atoibm-conv-spec-test",
     File::open("./test-resources/seq-byte-values-b632a992d3aed5d8d1a59cc5a5a455ba.test").unwrap(),
@@ -155,7 +177,7 @@ make_spec_test!(
     File::open("./test-resources/gnudd-conv-atoibm-seq-byte-values.spec").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     lcase_ascii_to_ucase_ascii,
     "lcase_ascii_to_ucase_ascii",
     File::open("./test-resources/lcase-ascii.test").unwrap(),
@@ -163,7 +185,7 @@ make_spec_test!(
     File::open("./test-resources/ucase-ascii.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     ucase_ascii_to_lcase_ascii,
     "ucase_ascii_to_lcase_ascii",
     File::open("./test-resources/ucase-ascii.test").unwrap(),
@@ -171,7 +193,7 @@ make_spec_test!(
     File::open("./test-resources/lcase-ascii.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     // conv=ebcdic,ucase
     atoe_and_ucase_conv_spec_test,
     "atoe-and-ucase-conv-spec-test",
@@ -180,7 +202,7 @@ make_spec_test!(
     File::open("./test-resources/ucase-ebcdic.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     // conv=ebcdic,lcase
     atoe_and_lcase_conv_spec_test,
     "atoe-and-lcase-conv-spec-test",
@@ -189,7 +211,7 @@ make_spec_test!(
     File::open("./test-resources/lcase-ebcdic.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     // conv=ibm,ucase
     atoibm_and_ucase_conv_spec_test,
     "atoibm-and-ucase-conv-spec-test",
@@ -198,7 +220,7 @@ make_spec_test!(
     File::open("./test-resources/lcase-ibm.test").unwrap()
 );
 
-make_spec_test!(
+make_conv_test!(
     // conv=ibm,lcase
     atoibm_and_lcase_conv_spec_test,
     "atoibm-and-lcase-conv-spec-test",
@@ -216,7 +238,7 @@ fn all_valid_ascii_ebcdic_ascii_roundtrip_conv_test()
 
     let i = Input {
         src: File::open("./test-resources/all-valid-ascii-chars-37eff01866ba3f538421b30b7cbefcac.test").unwrap(),
-        ibs: 256,
+        ibs: 128,
         xfer_stats: StatusLevel::None,
         cf: cfi!(Some(&ASCII_TO_EBCDIC)),
     };
@@ -266,3 +288,33 @@ fn all_valid_ascii_ebcdic_ascii_roundtrip_conv_test()
     fs::remove_file(&tmp_fname_ae).unwrap();
     fs::remove_file(&tmp_fname_ea).unwrap();
 }
+
+make_cfi_test!(
+    swab_256_test,
+    "swab-256",
+    File::open("./test-resources/seq-byte-values.test").unwrap(),
+    ConvFlagInput {
+        ctable: None,
+        block: false,
+        unblock: false,
+        swab: true,
+        sync: false,
+        noerror: false,
+    },
+    File::open("./test-resources/seq-byte-values-swapped.test").unwrap()
+);
+
+make_cfi_test!(
+    swab_257_test,
+    "swab-257",
+    File::open("./test-resources/seq-byte-values-odd.test").unwrap(),
+    ConvFlagInput {
+        ctable: None,
+        block: false,
+        unblock: false,
+        swab: true,
+        sync: false,
+        noerror: false,
+    },
+    File::open("./test-resources/seq-byte-values-odd.spec").unwrap()
+);
diff --git a/src/uu/dd/test-resources/seq-byte-values-swapped.test b/src/uu/dd/test-resources/seq-byte-values-swapped.test
index c86626638..be75933c8 100644
Binary files a/src/uu/dd/test-resources/seq-byte-values-swapped.test and b/src/uu/dd/test-resources/seq-byte-values-swapped.test differ