diff --git a/src/tests/test_condensed.py b/src/tests/test_condensed.py
new file mode 100644
--- /dev/null
+++ b/src/tests/test_condensed.py
@@ -0,0 +1,88 @@
+# GNU GPLv3, see LICENSE
+
+import os
+import random
+from unittest import TestCase
+
+from gf256 import _gfmul,evaluate
+from shamira import generateRaw,generate
+from condensed import *
+
+
+class TestCondensed(TestCase):
+	_urandom=os.urandom
+
+	@classmethod
+	def setUpClass(cls):
+		random.seed(17)
+		os.urandom=lambda n: bytes(random.randint(0,255) for i in range(n))
+
+	@classmethod
+	def tearDownClass(cls):
+		os.urandom=cls._urandom
+
+	def testGfmul(self):
+		for a in range(256):
+			for b in range(256):
+				self.assertEqual(_gfmul(a,b), gfmul(a,b))
+
+	def testGetConstantCoef(self):
+		self.assertEqual(getConstantCoef((1,1),(2,2),(3,3)), 0)
+
+		random.seed(17)
+		randomMatches=0
+		for i in range(10):
+			k=random.randint(2,255)
+
+			# exact
+			res=self.checkCoefsMatch(k,k)
+			self.assertEqual(res[0], res[1])
+
+			# overdetermined
+			res=self.checkCoefsMatch(k,256)
+			self.assertEqual(res[0], res[1])
+
+			# underdetermined => random
+			res=self.checkCoefsMatch(k,k-1)
+			if res[0]==res[1]:
+				randomMatches+=1
+		self.assertLess(randomMatches, 2) # with a chance (255/256)**10=0.96 there should be no match
+
+	def checkCoefsMatch(self,k,m):
+		coefs=[random.randint(0,255) for i in range(k)]
+		points=[(j, evaluate(coefs,j)) for j in range(1,256)]
+		random.shuffle(points)
+		return (getConstantCoef(*points[:m]), coefs[0])
+
+	def testGenerateReconstructRaw(self):
+		for (k,n) in [(2,3), (254,254)]:
+			shares=generateRaw(b"abcd",k,n)
+			random.shuffle(shares)
+			self.assertEqual(reconstructRaw(*shares[:k]), b"abcd")
+			self.assertNotEqual(reconstructRaw(*shares[:k-1]), b"abcd")
+
+	def testGenerateReconstruct(self):
+		for secret in ["abcde","ěščřžý"]:
+			for (k,n) in [(2,3), (254,254)]:
+				with self.subTest(sec=secret,k=k,n=n):
+					shares=generate(secret,k,n)
+					random.shuffle(shares)
+					self.assertEqual(reconstruct(*shares[:k]), secret)
+					try:
+						self.assertNotEqual(reconstruct(*shares[:k-1]), secret)
+					except UnicodeDecodeError:
+						pass
+		shares=generate(b"\xfeaa",2,3)
+		with self.assertRaises(UnicodeDecodeError):
+			reconstruct(*shares)
+
+	def testDecode(self):
+		with self.assertRaises(ValueError):
+			decode("AAA")
+			decode("1.")
+			decode(".AAA")
+			decode("1AAA")
+			decode("1.AAAQEAY")
+			decode("1.AAAQEAy=")
+			decode("256.AAAQEAY=")
+		self.assertEqual(decode("2.AAAQEAY="), (2,b"\x00\x01\x02\x03"))