diff --git a/README.rst b/README.rst
index 7d297dea..7a8e2a1b 100644
--- a/README.rst
+++ b/README.rst
@@ -46,6 +46,14 @@ Read and deserialize rosbag2 messages:
             print(msg.header.frame_id)
 
 
+Convert rosbag1 to rosbag2::
+
+   # Convert "foo.bag", result will be "foo/"
+   rosbags-convert foo.bag
+
+   # Convert "foo.bag", save the result as "bar"
+   rosbags-convert foo.bag --dst /path/to/bar
+
 
 Documentation
 =============
diff --git a/docs/api/rosbags.convert.rst b/docs/api/rosbags.convert.rst
new file mode 100644
index 00000000..ae336cf1
--- /dev/null
+++ b/docs/api/rosbags.convert.rst
@@ -0,0 +1,6 @@
+rosbags.convert
+===============
+
+.. automodule:: rosbags.convert
+   :members:
+   :show-inheritance:
diff --git a/docs/api/rosbags.rst b/docs/api/rosbags.rst
index 2dca8d05..19c8a4f3 100644
--- a/docs/api/rosbags.rst
+++ b/docs/api/rosbags.rst
@@ -4,6 +4,7 @@ Rosbags namespace
 .. toctree::
    :maxdepth: 4
 
+   rosbags.convert
    rosbags.rosbag1
    rosbags.rosbag2
    rosbags.serde
diff --git a/docs/index.rst b/docs/index.rst
index 583a285e..904b22ff 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -14,6 +14,7 @@
    topics/serde
    topics/rosbag2
    topics/rosbag1
+   topics/convert
 
 
 .. toctree::
diff --git a/docs/topics/convert.rst b/docs/topics/convert.rst
new file mode 100644
index 00000000..c4d2014d
--- /dev/null
+++ b/docs/topics/convert.rst
@@ -0,0 +1,29 @@
+Convert Rosbag1 to Rosbag2
+==========================
+
+The :py:mod:`rosbags.convert` package includes a CLI tool to convert legacy rosbag1 files to rosbag2.
+
+Features
+--------
+
+- Reasonably fast, as it converts raw ROS1 messages to raw CDR messages without going though deserialization and serialization
+- Tries to match ROS1 message type names to registered ROS2 types
+- Automatically registers unknown message types present in the legacy rosbag file for the conversion
+- Handles differences of ``std_msgs/msg/Header`` between both ROS versions
+
+Limitations
+-----------
+
+- Refuses to convert unindexed rosbag files, please reindex files before conversion
+- Currently does not handle split bags
+
+Usage
+-----
+
+.. code-block:: console
+
+   # Convert "foo.bag", result will be "foo/"
+   $ rosbags-convert foo.bag
+
+   # Convert "foo.bag", save the result as "bar"
+   $ rosbags-convert foo.bag --dst /path/to/bar
diff --git a/setup.cfg b/setup.cfg
index 7b70f9fd..21c5151c 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -54,6 +54,10 @@ install_requires =
     ruamel.yaml
     zstandard
 
+[options.entry_points]
+console_scripts =
+    rosbags-convert = rosbags.convert.__main__:main
+
 [options.extras_require]
 dev =
     darglint
diff --git a/src/rosbags/convert/__init__.py b/src/rosbags/convert/__init__.py
new file mode 100644
index 00000000..e4eddce0
--- /dev/null
+++ b/src/rosbags/convert/__init__.py
@@ -0,0 +1,16 @@
+# Copyright 2020-2021  Ternaris.
+# SPDX-License-Identifier: Apache-2.0
+"""Rosbags file format conversion.
+
+Conversion function transforms files from rosbag1 format to the latest rosbag2
+format. It automatically matches ROS1 message types to their ROS2 counterparts
+and adds custom types not present in the type system.
+
+"""
+
+from .converter import ConverterError, convert
+
+__all__ = [
+    'ConverterError',
+    'convert',
+]
diff --git a/src/rosbags/convert/__main__.py b/src/rosbags/convert/__main__.py
new file mode 100644
index 00000000..2ab89904
--- /dev/null
+++ b/src/rosbags/convert/__main__.py
@@ -0,0 +1,62 @@
+# Copyright 2020-2021  Ternaris.
+# SPDX-License-Identifier: Apache-2.0
+"""CLI tool for rosbag conversion."""
+
+from __future__ import annotations
+
+import argparse
+import sys
+from pathlib import Path
+from typing import TYPE_CHECKING
+
+from .converter import ConverterError, convert
+
+if TYPE_CHECKING:
+    from typing import Callable
+
+
+def pathtype(exists: bool = True) -> Callable:
+    """Path argument for argparse.
+
+    Args:
+        exists: Path should exists in filesystem.
+
+    Returns:
+        Argparse type function.
+
+    """
+
+    def topath(pathname: str) -> Path:
+        path = Path(pathname)
+        if exists != path.exists():
+            raise argparse.ArgumentTypeError(
+                f'{path} should {"exist" if exists else "not exist"}.',
+            )
+        return path
+
+    return topath
+
+
+def main() -> None:
+    """Parse cli arguments and run conversion."""
+    parser = argparse.ArgumentParser(description='Convert rosbag1 to rosbag2.')
+    parser.add_argument(
+        'src',
+        type=pathtype(),
+        help='source path to read rosbag1 from',
+    )
+    parser.add_argument(
+        '--dst',
+        type=pathtype(exists=False),
+        help='destination path for rosbag2',
+    )
+    args = parser.parse_args()
+    try:
+        convert(args.src, args.dst)
+    except ConverterError as err:
+        print(f'ERROR: {err}')  # noqa: T001
+        sys.exit(1)
+
+
+if __name__ == '__main__':
+    main()
diff --git a/src/rosbags/convert/converter.py b/src/rosbags/convert/converter.py
new file mode 100644
index 00000000..f1e4e9f3
--- /dev/null
+++ b/src/rosbags/convert/converter.py
@@ -0,0 +1,55 @@
+# Copyright 2020-2021  Ternaris.
+# SPDX-License-Identifier: Apache-2.0
+"""Rosbag1 to Rosbag2 Converter."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from rosbags.rosbag1 import Reader, ReaderError
+from rosbags.rosbag2 import Writer, WriterError
+from rosbags.serde import ros1_to_cdr
+from rosbags.typesys import get_types_from_msg, register_types
+
+if TYPE_CHECKING:
+    from pathlib import Path
+    from typing import Any, Dict, Optional
+
+
+class ConverterError(Exception):
+    """Converter Error."""
+
+
+def convert(src: Path, dst: Optional[Path]) -> None:
+    """Convert Rosbag1 to Rosbag2.
+
+    Args:
+        src: Rosbag1 path.
+        dst: Rosbag2 path.
+
+    Raises:
+        ConverterError: An error occured during reading, writing, or
+            converting.
+
+    """
+    dst = dst if dst else src.with_suffix('')
+    if dst.exists():
+        raise ConverterError(f'Output path {str(dst)!r} exists already.')
+
+    try:
+        with Reader(src) as reader, Writer(dst) as writer:
+            typs: Dict[str, Any] = {}
+            for name, topic in reader.topics.items():
+                writer.add_topic(name, topic.msgtype)
+                typs.update(get_types_from_msg(topic.msgdef, topic.msgtype))
+            register_types(typs)
+
+            for topic, msgtype, timestamp, data in reader.messages():
+                data = ros1_to_cdr(data, msgtype)
+                writer.write(topic, timestamp, data)
+    except ReaderError as err:
+        raise ConverterError(f'Reading source bag: {err}') from err
+    except WriterError as err:
+        raise ConverterError(f'Writing destination bag: {err}') from err
+    except Exception as err:  # pylint: disable=broad-except
+        raise ConverterError(f'Converting rosbag: {err!r}') from err
diff --git a/tests/test_convert.py b/tests/test_convert.py
new file mode 100644
index 00000000..1d015f35
--- /dev/null
+++ b/tests/test_convert.py
@@ -0,0 +1,109 @@
+# Copyright 2020-2021  Ternaris.
+# SPDX-License-Identifier: Apache-2.0
+"""Rosbag1to2 converter tests."""
+
+import sys
+from pathlib import Path
+from unittest.mock import Mock, patch
+
+import pytest
+
+from rosbags.convert import ConverterError, convert
+from rosbags.convert.__main__ import main
+from rosbags.rosbag1 import ReaderError
+from rosbags.rosbag2 import WriterError
+
+
+def test_cliwrapper(tmp_path: Path):
+    """Test cli wrapper."""
+    (tmp_path / 'subdir').mkdir()
+    (tmp_path / 'ros1.bag').write_text('')
+
+    with patch('rosbags.convert.__main__.convert') as cvrt, \
+         patch.object(sys, 'argv', ['cvt']), \
+         pytest.raises(SystemExit):
+        main()
+    assert not cvrt.called
+
+    with patch('rosbags.convert.__main__.convert') as cvrt, \
+         patch.object(sys, 'argv', ['cvt', str(tmp_path / 'no.bag')]), \
+         pytest.raises(SystemExit):
+        main()
+    assert not cvrt.called
+
+    with patch('rosbags.convert.__main__.convert') as cvrt, \
+         patch.object(sys, 'argv', ['cvt', str(tmp_path / 'ros1.bag')]):
+        main()
+    cvrt.assert_called_with(tmp_path / 'ros1.bag', None)
+
+    with patch('rosbags.convert.__main__.convert') as cvrt, \
+         patch.object(sys, 'argv', ['cvt',
+                                    str(tmp_path / 'ros1.bag'),
+                                    '--dst',
+                                    str(tmp_path / 'subdir')]), \
+         pytest.raises(SystemExit):
+        main()
+    assert not cvrt.called
+
+    with patch('rosbags.convert.__main__.convert') as cvrt, \
+         patch.object(sys, 'argv', ['cvt',
+                                    str(tmp_path / 'ros1.bag'),
+                                    '--dst',
+                                    str(tmp_path / 'target')]):
+        main()
+    cvrt.assert_called_with(tmp_path / 'ros1.bag', tmp_path / 'target')
+
+    with patch.object(sys, 'argv', ['cvt', str(tmp_path / 'ros1.bag')]), \
+         patch('builtins.print') as mock_print, \
+         patch('rosbags.convert.__main__.convert', side_effect=ConverterError('exc')), \
+         pytest.raises(SystemExit):
+        main()
+    mock_print.assert_called_with('ERROR: exc')
+
+
+def test_convert(tmp_path: Path):
+    """Test conversion function."""
+    (tmp_path / 'subdir').mkdir()
+    (tmp_path / 'foo.bag').write_text('')
+
+    with pytest.raises(ConverterError, match='exists already'):
+        convert(Path('foo.bag'), tmp_path / 'subdir')
+
+    with patch('rosbags.convert.converter.Reader') as reader, \
+         patch('rosbags.convert.converter.Writer') as writer, \
+         patch('rosbags.convert.converter.get_types_from_msg', return_value={'typ': 'def'}), \
+         patch('rosbags.convert.converter.register_types') as register_types, \
+         patch('rosbags.convert.converter.ros1_to_cdr') as ros1_to_cdr:
+
+        reader.return_value.__enter__.return_value.topics = {
+            '/topic': Mock(msgtype='typ', msgdef='def'),
+        }
+        reader.return_value.__enter__.return_value.messages.return_value = [
+            ('/topic', 'typ', 42, b'\x42'),
+        ]
+
+        ros1_to_cdr.return_value = b'666'
+
+        convert(Path('foo.bag'), None)
+
+        reader.assert_called_with(Path('foo.bag'))
+        reader.return_value.__enter__.return_value.messages.assert_called_with()
+
+        writer.assert_called_with(Path('foo'))
+        writer.return_value.__enter__.return_value.add_topic.assert_called_with('/topic', 'typ')
+        writer.return_value.__enter__.return_value.write.assert_called_with('/topic', 42, b'666')
+
+        register_types.assert_called_with({'typ': 'def'})
+        ros1_to_cdr.assert_called_with(b'\x42', 'typ')
+
+        ros1_to_cdr.side_effect = KeyError('exc')
+        with pytest.raises(ConverterError, match='Converting rosbag: '):
+            convert(Path('foo.bag'), None)
+
+        writer.side_effect = WriterError('exc')
+        with pytest.raises(ConverterError, match='Writing destination bag: '):
+            convert(Path('foo.bag'), None)
+
+        reader.side_effect = ReaderError('exc')
+        with pytest.raises(ConverterError, match='Reading source bag: '):
+            convert(Path('foo.bag'), None)