diff --git a/LICENSE b/LICENSE
index f2a3b9d..69fafad 100644
--- a/LICENSE
+++ b/LICENSE
@@ -25,9 +25,8 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 -------------------------------------------------------------------------------
 
-Files buffer.h, url.h, url_idna.cpp, url_percent_encode.cpp,
-url_percent_encode.h contains portions of modified code from the Chromium
-project licensed as follows:
+Files buffer.h, url.h, url_percent_encode.cpp, url_percent_encode.h contains
+portions of modified code from the Chromium project licensed as follows:
 
 // Copyright 2015 The Chromium Authors. All rights reserved.
 //
diff --git a/include/upa/url_idna.h b/include/upa/url_idna.h
deleted file mode 100644
index 3d84875..0000000
--- a/include/upa/url_idna.h
+++ /dev/null
@@ -1,74 +0,0 @@
-// Copyright 2016-2024 Rimas Misevičius
-// Distributed under the BSD-style license that can be
-// found in the LICENSE file.
-//
-
-#ifndef UPA_URL_IDNA_H
-#define UPA_URL_IDNA_H
-
-#include "buffer.h"
-#include "url_result.h"
-#include <cstddef>
-
-namespace upa {
-
-/// @brief Implements the domain to ASCII algorithm
-///
-/// See: https://url.spec.whatwg.org/#concept-domain-to-ascii
-/// This function does not have a boolean @a beStrict parameter and acts as if it were false.
-///
-/// @param[in]  src input domain string
-/// @param[in]  src_len input domain string length
-/// @param[out] output buffer to store result string
-/// @return `validation_errc::ok` on success, or error code on failure
-validation_errc domain_to_ascii(const char16_t* src, std::size_t src_len, simple_buffer<char16_t>& output);
-
-/// @brief Implements the domain to Unicode algorithm
-///
-/// See: https://url.spec.whatwg.org/#concept-domain-to-unicode
-/// This function does not have a boolean @a beStrict parameter and acts as if it were false.
-///
-/// @param[in]  src input domain string
-/// @param[in]  src_len input domain string length
-/// @param[out] output buffer to store result string
-/// @return `validation_errc::ok` on success, or error code on failure
-validation_errc domain_to_unicode(const char* src, std::size_t src_len, simple_buffer<char>& output);
-
-/// @brief Gets Unicode version that IDNA library conforms to
-///
-/// @return encoded Unicode version
-/// @see make_unicode_version
-unsigned idna_unicode_version();
-
-/// @brief Encodes Unicode version
-///
-/// The version is encoded as follows: <version 1st number> * 0x1000000 +
-/// <version 2nd number> * 0x10000 + <version 3rd number> * 0x100 + <version 4th number>
-///
-/// For example for Unicode version 15.1.0 it returns 0x0F010000
-///
-/// @param[in] n1 version 1st number
-/// @param[in] n2 version 2nd number
-/// @param[in] n3 version 3rd number
-/// @param[in] n4 version 4th number
-/// @return encoded Unicode version
-constexpr unsigned make_unicode_version(unsigned n1, unsigned n2 = 0,
-    unsigned n3 = 0, unsigned n4 = 0) noexcept {
-    return n1 << 24 | n2 << 16 | n3 << 8 | n4;
-}
-
-/// @brief Close the IDNA handles, conditionally close the IDNA library, and free its memory
-///
-/// It closes IDNA handles opened by calls to domain_to_ascii or domain_to_unicode functions.
-/// If @a close_lib is `true`, it closes the IDNA library (currently it calls the `u_cleanup`
-/// ICU function).
-///
-/// After calling this function, the `domain_to_ascii` and `domain_to_unicode` functions must
-/// not be called. So it is recommended to call this function at the end of an application.
-///
-/// @param[in] close_lib `true` to close the IDNA library (currently ICU)
-void idna_close(bool close_lib = false);
-
-} // namespace upa
-
-#endif // UPA_URL_IDNA_H