diff --git a/tests/zernike/test_zernike.py b/tests/zernike/test_zernike.py
new file mode 100644
index 0000000..fff4d38
--- /dev/null
+++ b/tests/zernike/test_zernike.py
@@ -0,0 +1,39 @@
+import pytest
+import numpy as np
+import lentil
+
+
+def test_zernike_rho_theta():
+    with pytest.raises(ValueError):
+        lentil.zernike.zernike(mask=1, index=1, normalize=True, rho=1, theta=None)
+
+
+def test_zernike_index():
+    with pytest.raises(ValueError):
+        lentil.zernike.zernike_index(-1)
+
+
+def test_zernike_basis():
+    basis = lentil.zernike.zernike_basis(mask=np.ones((3, 3)), modes=1, vectorize=False)
+    assert np.array_equal(basis, np.ones((1, 3, 3)))
+
+
+def test_zernike_basis_vectorize():
+    basis = lentil.zernike.zernike_basis(mask=np.ones((3, 3)), modes=1, vectorize=True)
+    assert np.array_equal(basis, np.ones((1, 9)))
+
+
+def test_zernike_fit():
+    mask = lentil.util.circlemask((256, 256), 128)
+    coeffs = np.random.rand(4)*100e-9
+    phase = lentil.zernike.zernike_compose(mask, coeffs)
+    fit_coeffs = lentil.zernike.zernike_fit(phase, mask, np.arange(1, 5))
+    assert np.all(np.isclose(coeffs, fit_coeffs))
+
+
+def test_zernike_remove():
+    mask = lentil.util.circlemask((256, 256), 128)
+    coeffs = np.random.rand(4)*100e-9
+    phase = lentil.zernike.zernike_compose(mask, coeffs)
+    residual = lentil.zernike.zernike_remove(phase, mask, np.arange(1, 5))
+    assert np.all(np.isclose(residual, np.zeros_like(residual)))