diff --git a/caput/tests/test_tools.py b/caput/tests/test_tools.py
new file mode 100644
index 00000000..4b50db96
--- /dev/null
+++ b/caput/tests/test_tools.py
@@ -0,0 +1,47 @@
+"""Unit tests for the tools module."""
+
+import numpy as np
+
+from caput import tools, mpiarray
+
+
+def test_allequal():
+    # Test some basic types
+    assert tools.allequal(1, 1)
+    assert tools.allequal("x", "x")
+    assert tools.allequal([1, 2, 3], [1, 2, 3])
+    assert tools.allequal({"a": 1}, {"a": 1})
+    assert tools.allequal({1, 2, 3}, {1, 2, 3})
+    assert tools.allequal((1, 2, 3), (1, 2, 3))
+
+    # Test numpy arrays and mpiarrays
+    assert tools.allequal(np.array([1, 2, 3]), np.array([1, 2, 3]))
+    assert tools.allequal(
+        mpiarray.MPIArray.wrap(np.array([1, 2, 3]), axis=0),
+        mpiarray.MPIArray.wrap(np.array([1, 2, 3]), axis=0),
+    )
+    assert tools.allequal(
+        np.array([1, 2, 3]),
+        mpiarray.MPIArray.wrap(np.array([1, 2, 3]), axis=0),
+    )
+
+    # Test objects with numpy arrays in them
+    assert tools.allequal(
+        [np.array([1]), np.array([2])], [np.array([1]), np.array([2])]
+    )
+    assert tools.allequal({"a": np.array([1])}, {"a": np.array([1])})
+
+    # Test objects with different types
+    assert tools.allequal([1, 3.4, "a"], [1, 3.4, "a"])
+
+    # Test for items that are not equal
+    assert not tools.allequal(1, 3)
+    assert not tools.allequal(1, 1.1)
+    assert not tools.allequal([np.array([1])], [np.array([2])])
+    assert not tools.allequal(
+        np.array(["x"], dtype="U32"), np.array(["x"], dtype="S32")
+    )
+
+    # Test for lengths that are not equal
+    assert not tools.allequal([1], [1, 2])
+    assert not tools.allequal({"a": 1}, {"a": 1, "b": 2})