diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index 1466e37..713bcf2 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -22,9 +22,14 @@ jobs:
         python-version: ${{ matrix.python-version }}
     - name: Install package
       run: |
-        python -m pip install --upgrade pip
-        python -m pip install --upgrade setuptools
+        python -m pip install --upgrade build pip setuptools twine
         python -m pip install .
     - name: Run test
       run: |
         python tests/test_mnemonic.py
+    - name: Build wheel and sdist
+      run: |
+        python -m build
+    - name: Check long description
+      run: |
+        twine check dist/*
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index db59742..5bad96f 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -8,6 +8,17 @@ All notable changes to this project will be documented in this file.
 The format is based on `Keep a Changelog`_, and this project adheres to
 `Semantic Versioning`_.
 
+`0.22`_ - Unreleased
+--------------------
+
+.. _0.22: https://github.com/trezor/python-mnemonic/compare/v0.21...HEAD
+
+Added
+~~~~~
+
+- Command-line interface with ``create``, ``check``, and ``to-seed`` commands
+- Click as a runtime dependency
+
 `0.21`_ - 2024-01-05
 --------------------
 
diff --git a/README.rst b/README.rst
index b2f652e..2e301fd 100644
--- a/README.rst
+++ b/README.rst
@@ -7,28 +7,31 @@ python-mnemonic
 Reference implementation of BIP-0039: Mnemonic code for generating
 deterministic keys
 
+Maintained by `Trezor <https://trezor.io>`_. See the `GitHub repository <https://github.com/trezor/python-mnemonic>`_ for source code and issue tracking.
+
 Abstract
 --------
 
 This BIP describes the implementation of a mnemonic code or mnemonic sentence --
 a group of easy to remember words -- for the generation of deterministic wallets.
 
-It consists of two parts: generating the mnenomic, and converting it into a
+It consists of two parts: generating the mnemonic, and converting it into a
 binary seed. This seed can be later used to generate deterministic wallets using
 BIP-0032 or similar methods.
 
 BIP Paper
 ---------
 
-See https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki
-for full specification
+See `BIP-0039`_ for the full specification.
 
 Installation
 ------------
 
 To install this library and its dependencies use:
 
- ``pip install mnemonic``
+.. code-block:: sh
+
+   $ pip install mnemonic
 
 Usage examples
 --------------
@@ -75,3 +78,43 @@ Given the word list, calculate original entropy:
 .. code-block:: python
 
    entropy = mnemo.to_entropy(words)
+
+Command-line interface
+----------------------
+
+The ``mnemonic`` command provides CLI access to the library:
+
+.. code-block:: sh
+
+   $ mnemonic create --help
+   $ mnemonic check --help
+   $ mnemonic to-seed --help
+
+Generate a new mnemonic phrase:
+
+.. code-block:: sh
+
+   $ mnemonic create
+   $ mnemonic create -s 256 -l english -p "my passphrase"
+   $ mnemonic create -s 256 -l english
+   $ mnemonic create -P                  # prompt for passphrase (hidden input)
+   $ mnemonic create --hide-seed         # only output mnemonic, not the seed
+   $ MNEMONIC_PASSPHRASE="secret" mnemonic create
+
+Validate a mnemonic phrase:
+
+.. code-block:: sh
+
+   $ mnemonic check abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about
+   $ echo "abandon abandon ..." | mnemonic check
+
+Derive seed from a mnemonic phrase:
+
+.. code-block:: sh
+
+   $ mnemonic to-seed abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about
+   $ mnemonic to-seed -p "my passphrase" word1 word2 ...
+   $ mnemonic to-seed -P word1 word2 ...   # prompt for passphrase (hidden input)
+   $ MNEMONIC_PASSPHRASE="secret" mnemonic to-seed word1 word2 ...
+
+.. _BIP-0039: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki
diff --git a/pyproject.toml b/pyproject.toml
index d99cb0f..b85db29 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -18,6 +18,10 @@ include = [
 
 [tool.poetry.dependencies]
 python = ">=3.8.1"
+click = "^8.0"
+
+[tool.poetry.scripts]
+mnemonic = "mnemonic.cli:cli"
 
 [tool.poetry.group.dev.dependencies]
 isort = "^5.13.2"
diff --git a/src/mnemonic/cli.py b/src/mnemonic/cli.py
new file mode 100644
index 0000000..997bdb6
--- /dev/null
+++ b/src/mnemonic/cli.py
@@ -0,0 +1,168 @@
+import sys
+
+import click
+
+from mnemonic import Mnemonic
+from mnemonic.mnemonic import ConfigurationError
+
+
+@click.group()
+def cli() -> None:
+    """BIP-39 mnemonic phrase generator and validator."""
+    pass
+
+
+@cli.command()
+@click.option(
+    "-l",
+    "--language",
+    default="english",
+    type=str,
+    help="Language for the mnemonic wordlist.",
+)
+@click.option(
+    "-s",
+    "--strength",
+    default="128",
+    type=click.Choice(["128", "160", "192", "224", "256"]),
+    help="Entropy strength in bits.",
+)
+@click.option(
+    "-p",
+    "--passphrase",
+    default="",
+    envvar="MNEMONIC_PASSPHRASE",
+    type=str,
+    help="Passphrase for seed derivation. Can also be set via MNEMONIC_PASSPHRASE env var.",
+)
+@click.option(
+    "-P",
+    "--prompt-passphrase",
+    is_flag=True,
+    default=False,
+    help="Prompt for passphrase with hidden input (secure).",
+)
+@click.option(
+    "--hide-seed",
+    is_flag=True,
+    default=False,
+    help="Do not display the derived seed.",
+)
+def create(
+    language: str,
+    passphrase: str,
+    prompt_passphrase: bool,
+    strength: str,
+    hide_seed: bool,
+) -> None:
+    """Generate a new mnemonic phrase and its derived seed."""
+    if prompt_passphrase:
+        if passphrase:
+            click.secho(
+                "Warning: --prompt-passphrase overrides -p/MNEMONIC_PASSPHRASE.",
+                fg="yellow",
+                err=True,
+            )
+        passphrase = click.prompt("Passphrase", default="", hide_input=True)
+    try:
+        mnemo = Mnemonic(language)
+        words = mnemo.generate(int(strength))
+        click.echo(f"Mnemonic: {words}")
+        if not hide_seed:
+            seed = mnemo.to_seed(words, passphrase)
+            click.echo(f"Seed: {seed.hex()}")
+    except ConfigurationError as e:
+        raise click.ClickException(str(e))
+
+
+@cli.command()
+@click.option(
+    "-l",
+    "--language",
+    default=None,
+    type=str,
+    help="Language for the mnemonic wordlist. Auto-detected if not specified.",
+)
+@click.argument("words", nargs=-1)
+def check(language: str | None, words: tuple[str, ...]) -> None:
+    """Validate a mnemonic phrase's checksum.
+
+    WORDS can be provided as arguments or piped via stdin.
+    """
+    if words:
+        mnemonic = " ".join(words)
+    else:
+        mnemonic = sys.stdin.read().strip()
+
+    if not mnemonic:
+        raise click.ClickException("No mnemonic provided.")
+
+    try:
+        if language is None:
+            language = Mnemonic.detect_language(mnemonic)
+        mnemo = Mnemonic(language)
+        if mnemo.check(mnemonic):
+            click.secho("Valid mnemonic.", fg="green")
+        else:
+            raise click.ClickException("Invalid mnemonic checksum.")
+    except ConfigurationError as e:
+        raise click.ClickException(str(e))
+    except (ValueError, LookupError) as e:
+        raise click.ClickException(str(e))
+
+
+@cli.command("to-seed")
+@click.option(
+    "-p",
+    "--passphrase",
+    default="",
+    envvar="MNEMONIC_PASSPHRASE",
+    type=str,
+    help="Passphrase for seed derivation. Can also be set via MNEMONIC_PASSPHRASE env var.",
+)
+@click.option(
+    "-P",
+    "--prompt-passphrase",
+    is_flag=True,
+    default=False,
+    help="Prompt for passphrase with hidden input (secure).",
+)
+@click.argument("words", nargs=-1)
+def to_seed(passphrase: str, prompt_passphrase: bool, words: tuple[str, ...]) -> None:
+    """Derive a seed from a mnemonic phrase.
+
+    WORDS can be provided as arguments or piped via stdin.
+    Outputs the 64-byte seed in hexadecimal format.
+    """
+    if words:
+        mnemonic = " ".join(words)
+    else:
+        mnemonic = sys.stdin.read().strip()
+
+    if not mnemonic:
+        raise click.ClickException("No mnemonic provided.")
+
+    if prompt_passphrase:
+        if passphrase:
+            click.secho(
+                "Warning: --prompt-passphrase overrides -p/MNEMONIC_PASSPHRASE.",
+                fg="yellow",
+                err=True,
+            )
+        passphrase = click.prompt("Passphrase", default="", hide_input=True)
+
+    try:
+        language = Mnemonic.detect_language(mnemonic)
+        mnemo = Mnemonic(language)
+        if not mnemo.check(mnemonic):
+            raise click.ClickException("Invalid mnemonic checksum.")
+        seed = mnemo.to_seed(mnemonic, passphrase)
+        click.echo(seed.hex())
+    except ConfigurationError as e:
+        raise click.ClickException(str(e))
+    except (ValueError, LookupError) as e:
+        raise click.ClickException(str(e))
+
+
+if __name__ == "__main__":
+    cli()
diff --git a/tests/test_mnemonic.py b/tests/test_mnemonic.py
index 641cf16..48dd815 100755
--- a/tests/test_mnemonic.py
+++ b/tests/test_mnemonic.py
@@ -26,7 +26,10 @@
 import unittest
 from typing import List
 
+from click.testing import CliRunner
+
 from mnemonic import Mnemonic
+from mnemonic.cli import cli
 
 
 class MnemonicTest(unittest.TestCase):
@@ -149,6 +152,139 @@ def test_expand(self) -> None:
         )
 
 
+class CLITest(unittest.TestCase):
+    def setUp(self) -> None:
+        self.runner = CliRunner()
+
+    def test_create_generates_valid_mnemonic(self) -> None:
+        result = self.runner.invoke(cli, ["create"])
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Mnemonic:", result.output)
+        self.assertIn("Seed:", result.output)
+        # Extract mnemonic and verify it's valid
+        mnemonic_line = result.output.split("\n")[0]
+        mnemonic = mnemonic_line.replace("Mnemonic: ", "")
+        mnemo = Mnemonic("english")
+        self.assertTrue(mnemo.check(mnemonic))
+
+    def test_create_with_strength(self) -> None:
+        result = self.runner.invoke(cli, ["create", "-s", "256"])
+        self.assertEqual(result.exit_code, 0)
+        mnemonic_line = result.output.split("\n")[0]
+        mnemonic = mnemonic_line.replace("Mnemonic: ", "")
+        # 256 bits = 24 words
+        self.assertEqual(len(mnemonic.split()), 24)
+
+    def test_create_invalid_strength(self) -> None:
+        result = self.runner.invoke(cli, ["create", "-s", "100"])
+        self.assertNotEqual(result.exit_code, 0)
+
+    def test_create_invalid_language(self) -> None:
+        result = self.runner.invoke(cli, ["create", "-l", "klingon"])
+        self.assertEqual(result.exit_code, 1)
+        self.assertIn("Error", result.output)
+
+    def test_check_valid_mnemonic(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["check"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Valid mnemonic", result.output)
+
+    def test_check_invalid_mnemonic(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon wrong"
+        result = self.runner.invoke(cli, ["check"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 1)
+        self.assertIn("Invalid mnemonic checksum", result.output)
+
+    def test_check_stdin(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["check"], input=mnemonic)
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Valid mnemonic", result.output)
+
+    def test_check_empty_input(self) -> None:
+        result = self.runner.invoke(cli, ["check"], input="")
+        self.assertEqual(result.exit_code, 1)
+        self.assertIn("No mnemonic provided", result.output)
+
+    def test_to_seed_valid_mnemonic(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["to-seed"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 0)
+        expected_seed = "5eb00bbddcf069084889a8ab9155568165f5c453ccb85e70811aaed6f6da5fc19a5ac40b389cd370d086206dec8aa6c43daea6690f20ad3d8d48b2d2ce9e38e4"
+        self.assertEqual(result.output.strip(), expected_seed)
+
+    def test_to_seed_with_passphrase(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["to-seed", "-p", "TREZOR"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 0)
+        expected_seed = "c55257c360c07c72029aebc1b53c05ed0362ada38ead3e3e9efa3708e53495531f09a6987599d18264c1e1c92f2cf141630c7a3c4ab7c81b2f001698e7463b04"
+        self.assertEqual(result.output.strip(), expected_seed)
+
+    def test_to_seed_with_env_passphrase(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(
+            cli, ["to-seed"] + mnemonic.split(), env={"MNEMONIC_PASSPHRASE": "TREZOR"}
+        )
+        self.assertEqual(result.exit_code, 0)
+        expected_seed = "c55257c360c07c72029aebc1b53c05ed0362ada38ead3e3e9efa3708e53495531f09a6987599d18264c1e1c92f2cf141630c7a3c4ab7c81b2f001698e7463b04"
+        self.assertEqual(result.output.strip(), expected_seed)
+
+    def test_to_seed_invalid_mnemonic(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon wrong"
+        result = self.runner.invoke(cli, ["to-seed"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 1)
+        self.assertIn("Invalid mnemonic checksum", result.output)
+
+    def test_to_seed_stdin(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["to-seed"], input=mnemonic)
+        self.assertEqual(result.exit_code, 0)
+        expected_seed = "5eb00bbddcf069084889a8ab9155568165f5c453ccb85e70811aaed6f6da5fc19a5ac40b389cd370d086206dec8aa6c43daea6690f20ad3d8d48b2d2ce9e38e4"
+        self.assertEqual(result.output.strip(), expected_seed)
+
+    def test_check_with_language_option(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["check", "-l", "english"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Valid mnemonic", result.output)
+
+    def test_check_with_invalid_language(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(cli, ["check", "-l", "klingon"] + mnemonic.split())
+        self.assertEqual(result.exit_code, 1)
+
+    def test_create_with_prompt_passphrase(self) -> None:
+        result = self.runner.invoke(cli, ["create", "-P"], input="test_passphrase\n")
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Mnemonic:", result.output)
+        self.assertIn("Seed:", result.output)
+
+    def test_to_seed_with_prompt_passphrase(self) -> None:
+        mnemonic = "abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon abandon about"
+        result = self.runner.invoke(
+            cli, ["to-seed", "-P"] + mnemonic.split(), input="TREZOR\n"
+        )
+        self.assertEqual(result.exit_code, 0)
+        expected_seed = "c55257c360c07c72029aebc1b53c05ed0362ada38ead3e3e9efa3708e53495531f09a6987599d18264c1e1c92f2cf141630c7a3c4ab7c81b2f001698e7463b04"
+        self.assertIn(expected_seed, result.output)
+
+    def test_prompt_passphrase_warning_when_both_set(self) -> None:
+        result = self.runner.invoke(
+            cli,
+            ["create", "-p", "existing", "-P"],
+            input="new_passphrase\n",
+        )
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Warning", result.output)
+
+    def test_create_hide_seed(self) -> None:
+        result = self.runner.invoke(cli, ["create", "--hide-seed"])
+        self.assertEqual(result.exit_code, 0)
+        self.assertIn("Mnemonic:", result.output)
+        self.assertNotIn("Seed:", result.output)
+
+
 def __main__() -> None:
     unittest.main()