diff --git a/src/pytom_tm/entry_points.py b/src/pytom_tm/entry_points.py
index cfada29..a493f60 100644
--- a/src/pytom_tm/entry_points.py
+++ b/src/pytom_tm/entry_points.py
@@ -18,6 +18,7 @@
     ParseDoseFile,
     ParseDefocus,
     BetweenZeroAndOne,
+    ParseGPUIndices,
 )
 from pytom_tm.tmjob import load_json_to_tmjob
 from os import urandom
@@ -902,6 +903,7 @@ def match_template(argv=None):
         "--gpu-ids",
         nargs="+",
         type=int,
+        action=ParseGPUIndices,
         required=True,
         help="GPU indices to run the program on.",
     )
diff --git a/src/pytom_tm/io.py b/src/pytom_tm/io.py
index d57825c..0a1e8aa 100644
--- a/src/pytom_tm/io.py
+++ b/src/pytom_tm/io.py
@@ -150,6 +150,31 @@ def __call__(
             parser.error("{0} can only take one or two arguments".format(option_string))
 
 
+class ParseGPUIndices(argparse.Action):
+    """argparse.Action subclass to parse gpu indices. The input can either be an int or
+    a list of ints that specify the gpu indices to be used.
+    """
+
+    def __call__(
+        self,
+        parser,
+        namespace,
+        values: list[int, ...],
+        option_string: Optional[str] = None,
+    ):
+        import cupy
+
+        max_value = cupy.cuda.runtime.getDeviceCount()
+        for val in values:
+            if val < 0 or val >= max_value:
+                parser.error(
+                    f"{option_string} all gpu indices should be between 0 "
+                    "and {max_value-1}"
+                )
+
+        setattr(namespace, self.dest, values)
+
+
 class ParseDoseFile(argparse.Action):
     """argparse.Action subclass to parse a txt file contain information on accumulated
     dose per tilt."""
diff --git a/tests/test_entry_points.py b/tests/test_entry_points.py
index d52d23d..27557c3 100644
--- a/tests/test_entry_points.py
+++ b/tests/test_entry_points.py
@@ -1,6 +1,7 @@
 import unittest
 import pathlib
 import numpy as np
+import cupy as cp
 import logging
 from shutil import which
 from contextlib import redirect_stdout, redirect_stderr
@@ -43,7 +44,10 @@
 
 def prep_argv(arg_dict):
     argv = []
-    [argv.extend([k, v]) if v != "" else argv.append(k) for k, v in arg_dict.items()]
+    [
+        argv.extend([k] + v.split()) if v != "" else argv.append(k)
+        for k, v in arg_dict.items()
+    ]
     return argv
 
 
@@ -176,5 +180,20 @@ def start(arg_dict):  # simplify run
             msg="File should exist in debug mode",
         )
 
-        # rest the log level after the entry point modified it
+        # reset the log level after the entry point modified it
         logging.basicConfig(level=LOG_LEVEL, force=True)
+
+        # test providing invalid gpu indices
+        n_devices = cp.cuda.runtime.getDeviceCount()
+        for indices in ["-1", f"0 {n_devices}"]:
+            dump = StringIO()
+            with (
+                self.assertRaises(SystemExit) as ex,
+                redirect_stdout(dump),
+                redirect_stderr(dump),
+            ):
+                arguments = defaults.copy()
+                arguments["-g"] = indices
+                start(arguments)
+            self.assertIn("gpu indices", dump.getvalue())
+            dump.close()