diff --git a/.coveragerc b/.coveragerc
index 3880345..ac37284 100644
--- a/.coveragerc
+++ b/.coveragerc
@@ -1,3 +1,4 @@
 [run]
 omit =
     setup.py
+    perftest_ulid2.py
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 5609134..587a3b2 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -25,4 +25,5 @@ jobs:
           python-version: '${{ matrix.python-version }}'
       - run: pip install pytest pytest-cov
       - run: py.test -vvv --cov .
+      - run: python perftest_ulid2.py
       - uses: codecov/codecov-action@v2
diff --git a/perftest_ulid2.py b/perftest_ulid2.py
new file mode 100644
index 0000000..8ae38f0
--- /dev/null
+++ b/perftest_ulid2.py
@@ -0,0 +1,28 @@
+from __future__ import print_function
+import timeit
+
+import ulid2
+
+
+def perftest():
+    tmr = timeit.Timer(lambda: ulid2.generate_ulid_as_uuid())
+    n_iterations = 300000
+    time_taken = tmr.timeit(n_iterations)
+    return int(n_iterations / time_taken)
+
+
+def main():
+    results = []
+    for x in range(5):
+        ops_per_sec = perftest()
+        print(x + 1, " ... ", ops_per_sec)
+        results.append(ops_per_sec)
+    n_results = len(results)
+    mean = sum(results) / n_results
+    median = sorted(results)[n_results // 2]
+    print("mean ops/sec  ", mean)
+    print("median ops/sec", median)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/ulid2.py b/ulid2.py
index 0c5865a..f10337a 100644
--- a/ulid2.py
+++ b/ulid2.py
@@ -29,12 +29,12 @@ class InvalidULID(ValueError):
 
 
 def _to_binary(byte_list):
-    if py3:
-        return bytes(byte_list)
-    else:
-        return bytes(b''.join(chr(b) for b in byte_list))
+    return bytes(b''.join(chr(b) for b in byte_list))
 
 
+if py3:
+    _to_binary = bytes
+
 # Unrolled and optimized ULID Base32 encoding/decoding
 # implementations based on NUlid:
 # https://github.com/RobThree/NUlid/blob/5f2678b4d/NUlid/Ulid.cs#L159
@@ -173,6 +173,7 @@ def get_ulid_time(ulid):
 _last_entropy = None
 _last_timestamp = None
 
+
 def generate_binary_ulid(timestamp=None, monotonic=False):
     """
     Generate the bytes for an ULID.
@@ -193,9 +194,7 @@ def generate_binary_ulid(timestamp=None, monotonic=False):
         timestamp = calendar.timegm(timestamp.utctimetuple())
 
     ts = int(timestamp * 1000.0)
-    ts_bytes = _to_binary(
-        (ts >> shift) & 0xFF for shift in (40, 32, 24, 16, 8, 0)
-    )
+    ts_bytes = struct.pack('!Q', ts)[2:]
     entropy = os.urandom(10)
     if monotonic and _last_timestamp == ts and _last_entropy is not None:
         while entropy < _last_entropy: