diff --git a/README.md b/README.md
index b42c59e..77201e0 100644
--- a/README.md
+++ b/README.md
@@ -14,6 +14,8 @@ CertStreamMonitor architecture relies on 3 scripts :
   - it collects informations about the sites that are up to DB and to a JSON file.
 - `gethost.py`
    - Due to [@nbeguier](https://github.com/nbeguier) contribution, the project has also a `gethost.py` script that provides a way for security operators to request the last hostnames which have been detected by `certstreammointor.py` since X seconds.
+- `check_rules.py`
+   - Due to [@nbeguier](https://github.com/nbeguier) contribution, the project has also a `check_rules.py` script that provides a way for security operators to check their own rules, especially SearchKeywords, DetectionThreshold and BlacklistKeywords.
 
 ## Features
 - **Monitoring:**
@@ -129,6 +131,38 @@ socialmediaforsocialaction.com 2019-06-12T15:54:31
 social.socialbride.co.za None
 ~~~
 
+### check_rules.py
+
+~~~
+$ python3 check_rules.py --help
+
+    -h --help       Print this help
+    -c --config     Configuration file to use
+    -d --domain     Domain name to check
+~~~
+
+~~~
+# No match - Keywords not found.
+$ ./check_rules.py -c conf/example.conf -d www.google.com
+Looking for these strings: paypal|apple|account|secure|login, detection threshold: 2
+No match - Keywords not found.
+
+# No match - Detection threashold not reached.
+$ ./check_rules.py -c conf/example.conf -d paypal.com
+Looking for these strings: paypal|apple|account|secure|login, detection threshold: 2
+No match - Detection threashold not reached.
+
+# No match - Blacklisted keywords.
+$ ./check_rules.py -c conf/example.conf -d login-paypal.gouv
+Looking for these strings: paypal|apple|account|secure|login, detection threshold: 2
+No match - Blacklisted keywords.
+
+# This is a match, detection threashold reached.
+$ ./check_rules.py -c conf/example.conf -d login-paypal.com
+Looking for these strings: paypal|apple|account|secure|login, detection threshold: 2
+This is a match, detection threashold reached.
+~~~
+
 ## Authors
 - Thomas Damonneville ([thomas.damonneville@assurance-maladie.fr](mailto:thomas.damonneville@assurance-maladie.fr))
 - Christophe Brocas ([christophe.brocas@assurance-maladie.fr](mailto:christophe.brocas@assurance-maladie.fr))
diff --git a/check_rules.py b/check_rules.py
new file mode 100755
index 0000000..9151735
--- /dev/null
+++ b/check_rules.py
@@ -0,0 +1,143 @@
+#!/usr/bin/env python3
+
+# Copyright (c) 2018 Caisse nationale d'Assurance Maladie
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+import os
+import re
+import sys
+import getopt
+import logging
+from utils.confparser import ConfParser
+from utils.utils import VerifyPath
+
+VERSION = "0.0.1"
+
+def usage():
+    """
+    CLI usage printing
+    """
+    usage_output = """
+    -h --help       Print this help
+    -c --config     Configuration file to use
+    -d --domain     Domain name to check
+    """
+    print(usage_output)
+    sys.exit(0)
+
+
+def ConfAnalysis(configuration_file):
+    """
+    configuration file analysis. Load global variables with parameters found
+    in configuration file.
+
+    :param  configuration_file: the configuration file
+    """
+    global CONF
+    global SearchKeywords
+    global BlacklistKeywords
+    global DetectionThreshold
+
+    try:
+        CONF = ConfParser(configuration_file)
+
+        SearchKeywords = CONF.SearchKeywords
+        BlacklistKeywords = CONF.BlacklistKeywords
+        DetectionThreshold = CONF.DetectionThreshold
+    except:
+        err = sys.exc_info()
+        logging.error(" ConfParser Error: %s", err)
+
+
+def args_parse():
+    """
+    Tool options
+    """
+    global ConfFile
+    global DOMAIN
+    if not len(sys.argv[1:]):
+        usage()
+    try:
+        opts, _ = getopt.getopt(sys.argv[1:], "hc:d:", ["help", "conf="])
+    except getopt.GetoptError as err:
+        logging.error(" Option Error. Exiting... %s", err)
+        usage()
+        sys.exit(2)
+
+    DOMAIN = None
+    for o, a in opts:
+        if o in ("-h", "--help"):
+            usage()
+        elif o in ("-c", "--config"):
+            if os.path.isfile(a):
+                ConfFile = a
+            else:
+                logging.error(" Can't find configuration file. Exiting...")
+                sys.exit(1)
+        elif o in ("-d", "--domain"):
+            DOMAIN = a
+        else:
+            assert False, "Unhandled Option"
+    if not DOMAIN:
+        usage()
+        sys.exit(2)
+
+
+def print_callback():
+    """
+    Truncate CertStreamMonitor/print_callback function, SQL/Logging support removed
+    """
+    is_blacklisted = False
+    if BlacklistKeywords != str():
+        is_blacklisted = re.findall(BlacklistKeywords, DOMAIN)
+    results = re.findall(SearchKeywords, DOMAIN)
+    FindNb = len(set(results))
+
+    # Matching host whith blacklisted keywords are ignored
+    if is_blacklisted and FindNb >= DetectionThreshold:
+        logging.info("No match - Blacklisted keywords.")
+        return
+
+    # If search keywords occurence in the hostname is greater or equal to DetectionThreshold
+    if FindNb >= DetectionThreshold:
+        logging.info("This is a match, detection threashold reached.")
+    elif FindNb > 0 and FindNb < DetectionThreshold:
+        logging.info("No match - Detection threashold not reached.")
+    else:
+        logging.info("No match - Keywords not found.")
+    return
+
+
+# Main
+def main():
+    # Config
+    ConfAnalysis(ConfFile)
+    VerifyPath()
+
+    # logging
+    logger = logging.getLogger()
+    logger.setLevel(logging.DEBUG)
+
+    # term handler
+    stream_handler = logging.StreamHandler()
+    stream_handler.setLevel(logging.INFO)
+    logger.addHandler(stream_handler)
+    logging.info(
+        "Looking for these strings: %s, detection threshold: %s",
+        SearchKeywords,
+        DetectionThreshold)
+    print_callback()
+
+
+# Start
+if __name__ == '__main__':
+    args_parse()
+    main()
diff --git a/conf/example.conf b/conf/example.conf
index 91cb971..c67868b 100644
--- a/conf/example.conf
+++ b/conf/example.conf
@@ -14,7 +14,7 @@ DetectionThreshold = 2
 
 # Keywords to ignore matched hosts (with '|' (or) as separator).
 # Leave it empty or comment it to disable this feature.
-# BlacklistKeywords = mail\.|\.com|bitcoin
+BlacklistKeywords = mail\.|\.gouv|bitcoin
 
 [DATABASE]
 # SQLite3 database path (will be created if not exist)