diff --git a/rwa_wdm/io.py b/rwa_wdm/io.py
index e321a9c..92ac6ba 100644
--- a/rwa_wdm/io.py
+++ b/rwa_wdm/io.py
@@ -5,14 +5,16 @@
 import os
 import glob
 import logging
+from typing import List
 
 import numpy as np
 import matplotlib.pyplot as plt
 
-logger = logging.getLogger(__name__)  # noqa
+logger = logging.getLogger(__name__)
 
 
-def write_results_to_disk(result_dir, filename, bplist):
+def write_bp_to_disk(result_dir: str,
+                     filename: str, bplist: List[float]) -> None:
     """Write blocking probabilities to text file
 
     """
@@ -21,14 +23,29 @@ def write_results_to_disk(result_dir, filename, bplist):
         os.mkdir(result_dir)
 
     filepath = os.path.join(result_dir, filename)
-    logger.info('Writing results to file "%s"' % filepath)
+    logger.info('Writing blocking probability results to file "%s"' % filepath)
     with open(filepath, 'a') as f:
         for bp in bplist:
             f.write(' %7.3f' % bp)
         f.write('\n')
 
+def write_it_to_disk(result_dir: str,
+                     filename: str, itlist: List[float]) -> None:
+    """Write profiling time information to text file
 
-def plot_blocking_probability(result_dir):
+    """
+    if not os.path.isdir(result_dir):
+        logger.info('Creating result dir in %s' % result_dir)
+        os.mkdir(result_dir)
+
+    filepath = os.path.join(result_dir, filename)
+    logger.info('Writing simulation profiling times to file "%s"' % filepath)
+    with open(filepath, 'a') as f:
+        for it in itlist:
+            f.write(' %7.7f' % it)
+
+
+def plot_bp(result_dir: str) -> None:
     """Reads blocking probabilities from file and plot overlapping graph
 
     """
diff --git a/rwa_wdm/sim.py b/rwa_wdm/sim.py
index 8775d1c..a290feb 100644
--- a/rwa_wdm/sim.py
+++ b/rwa_wdm/sim.py
@@ -13,11 +13,12 @@
 # [1] https://la.mathworks.com/matlabcentral/fileexchange/4797-wdm-network-blocking-computation-toolbox
 
 import logging
+from timeit import default_timer  # https://stackoverflow.com/a/25823885/3798300
 from typing import Callable
 
 import numpy as np
 
-from .io import write_results_to_disk, plot_blocking_probability
+from .io import write_bp_to_disk, write_it_to_disk, plot_bp
 from .net import Network
 
 logger = logging.getLogger(__name__)
@@ -92,7 +93,9 @@ def simulator(args):
         print('%4d' % i, end=' ')
     print()
 
+    time_per_simulation = []
     for simulation in range(args.num_sim):
+        _sim_time = default_timer()
         net = get_net_instance_from_args(args.topology, args.channels)
         rwa = get_rwa_algorithm_from_args(args.r, args.w, args.rwa,
                                           args.pop_size, args.num_gen,
@@ -190,17 +193,22 @@ def simulator(args):
             blocklist.append(blocks)
             blocks_per_erlang.append(100.0 * blocks / args.calls)
 
+        _sim_time = default_timer() - _sim_time
+        time_per_simulation.append(_sim_time)
+
         print('\rBlocks: ', end='', flush=True)
         for b in blocklist:
             print('%04d ' % b, end='', flush=True)
         print('\n%-7s ' % net.name, end='')
         print(' '.join(['%4.1f' % b for b in blocks_per_erlang]))
 
-        filename = '%s_%dch_%dreq_%s.bp' % (
+        fbase = '%s_%dch_%dreq_%s' % (
             args.rwa if args.rwa is not None else '%s_%s' % (args.r, args.w),
             args.channels, args.calls, net.name)
 
-        write_results_to_disk(args.result_dir, filename, blocks_per_erlang)
+        write_bp_to_disk(args.result_dir, fbase + '.bp', blocks_per_erlang)
+
+    write_it_to_disk(args.result_dir, fbase + '.it', time_per_simulation)
 
     if args.plot:
-        plot_blocking_probability(args.result_dir)
+        plot_bp(args.result_dir)