diff --git a/tests/unit-tests/encoding/estimator.t.cpp b/tests/unit-tests/encoding/estimator.t.cpp
new file mode 100644
index 0000000..b759489
--- /dev/null
+++ b/tests/unit-tests/encoding/estimator.t.cpp
@@ -0,0 +1,120 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2015 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+ * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include "encoding/estimator.hpp"
+
+#include "boost-test.hpp"
+
+namespace ndn {
+namespace encoding {
+namespace tests {
+
+BOOST_AUTO_TEST_SUITE(EncodingEstimator)
+
+BOOST_AUTO_TEST_CASE(Basic)
+{
+  Estimator e;
+  Estimator e1(100);
+  Estimator e2(100, 100);
+
+  BOOST_CHECK_EQUAL(e.prependByte(1), 1);
+  BOOST_CHECK_EQUAL(e.appendByte(1), 1);
+
+  uint8_t buf1[] = {'t', 'e', 's', 't', '1'};
+  BOOST_CHECK_EQUAL(e1.prependByteArray(buf1, sizeof(buf1)), 5);
+  BOOST_CHECK_EQUAL(e1.appendByteArray(buf1, sizeof(buf1)), 5);
+
+  std::vector<uint8_t> buf2 = {'t', 'e', 's', 't', '2'};
+  BOOST_CHECK_EQUAL(e1.prependRange(buf2.begin(), buf2.end()), 5);
+  BOOST_CHECK_EQUAL(e1.appendRange(buf2.begin(), buf2.end()), 5);
+
+  std::list<uint8_t> buf3 = {'t', 'e', 's', 't', '2'};
+  BOOST_CHECK_EQUAL(e2.prependRange(buf3.begin(), buf3.end()), 5);
+  BOOST_CHECK_EQUAL(e2.appendRange(buf3.begin(), buf3.end()), 5);
+}
+
+BOOST_AUTO_TEST_CASE(Tlv)
+{
+  Estimator e;
+
+  BOOST_CHECK_EQUAL(e.prependVarNumber(1), 1);
+  BOOST_CHECK_EQUAL(e.appendVarNumber(1), 1);
+
+  BOOST_CHECK_EQUAL(e.prependVarNumber(252), 1);
+  BOOST_CHECK_EQUAL(e.appendVarNumber(252), 1);
+
+  BOOST_CHECK_EQUAL(e.prependVarNumber(253), 3);
+  BOOST_CHECK_EQUAL(e.appendVarNumber(253), 3);
+
+  BOOST_CHECK_EQUAL(e.prependVarNumber(65536), 5);
+  BOOST_CHECK_EQUAL(e.appendVarNumber(65536), 5);
+
+  BOOST_CHECK_EQUAL(e.prependVarNumber(4294967296LL), 9);
+  BOOST_CHECK_EQUAL(e.appendVarNumber(4294967296LL), 9);
+
+  //
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(1), 1);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(1), 1);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(252), 1);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(252), 1);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(253), 1);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(253), 1);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(255), 1);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(255), 1);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(256), 2);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(256), 2);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(65535), 2);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(65535), 2);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(65536), 4);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(65536), 4);
+
+  BOOST_CHECK_EQUAL(e.prependNonNegativeInteger(4294967296LL), 8);
+  BOOST_CHECK_EQUAL(e.appendNonNegativeInteger(4294967296LL), 8);
+
+  //
+
+  uint8_t buf[] = {0x01, 0x03, 0x00, 0x00, 0x00};
+  Block block1(buf, sizeof(buf));
+
+  BOOST_CHECK_EQUAL(e.prependByteArrayBlock(100, buf, sizeof(buf)), 7);
+  BOOST_CHECK_EQUAL(e.appendByteArrayBlock(100, buf, sizeof(buf)), 7);
+
+  BOOST_CHECK_EQUAL(e.prependBlock(block1), 5);
+  BOOST_CHECK_EQUAL(e.appendBlock(block1), 5);
+
+  Block block2(100, block1);
+
+  BOOST_CHECK_EQUAL(e.prependBlock(block2), 7);
+  BOOST_CHECK_EQUAL(e.appendBlock(block2), 7);
+}
+
+BOOST_AUTO_TEST_SUITE_END() // EncodingEstimator
+
+} // namespace tests
+} // namespace encoding
+} // namespace ndn