diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000..4e506e1
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,25 @@
+MIT License
+
+Copyright (c) 2026 Alex Cube
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+This license covers the code (index.html, check.mjs). It does not cover
+DLM_rukovodstvo_1987.pdf (scans and text of the 1987 booklet) or the card
+images in cards/ (cut from a third-party photo).
diff --git a/README.md b/README.md
index 45c5c43..48718a0 100644
--- a/README.md
+++ b/README.md
@@ -50,4 +50,9 @@ node check.mjs
 - Руководство — экземпляр автора, проданный вместе с машиной № 005957 23 февраля 1988 года.
 - Карточки вырезаны с фотографии полного набора, найденной в объявлении о продаже.
 
+## Лицензия
+
+Код (`index.html`, `check.mjs`) — [MIT](LICENSE). На руководство 1987 года и картинки карточек лицензия
+не распространяется.
+
 Основной репозиторий: https://git.08h.ru/alex/dlm, здесь зеркало.