diff --git a/sort_certificate.py b/sort_certificate.py
index a40bb2f..d147c8a 100755
--- a/sort_certificate.py
+++ b/sort_certificate.py
@@ -30,6 +30,70 @@ ASN1TIME_FMT = str('%Y%m%d%H%M%SZ'.encode('utf8'))
 OPENSSLTIME_FMT = '%b %e %T %Y GMT'
 
 
+class PkDecorator(object):
+    '''
+    Provide some information on the private key object
+    '''
+    pk = None
+
+    def __init__(self, pk):
+        self.pk = pk
+
+    def __str__(self):
+        return "Private key"
+
+
+class PkDecoratorEC(PkDecorator):
+
+    def __str__(self):
+        pk_crypto = self.pk.to_cryptography_key()
+        return "EC Private key curve %s (%d bits)" % (
+                pk_crypto.curve.name, pk_crypto.key_size)
+
+
+class PkDecoratorRSA(PkDecorator):
+
+    def __str__(self):
+        pk_crypto = self.pk.to_cryptography_key()
+        return "RSA Private key %d bits" % pk_crypto.key_size
+
+
+class PkDecoratorDSA(PkDecorator):
+
+    def __str__(self):
+        pk_crypto = self.pk.to_cryptography_key()
+        return "DSA Private key %d bits" % pk_crypto.key_size
+
+
+class PkDecoratorDH(PkDecorator):
+
+    def __str__(self):
+        pk_crypto = self.pk.to_cryptography_key()
+        return "DH Private key %d bits" % pk_crypto.key_size
+
+
+class PkDecoratorFactory(object):
+    '''
+    Provide some information on the private key object
+    '''
+
+    def create(pk):
+        '''
+        Create the appropriate decorater object
+        '''
+        decorators = {
+                crypto.TYPE_DH: PkDecoratorDH,
+                crypto.TYPE_EC: PkDecoratorEC,
+                crypto.TYPE_DSA: PkDecoratorDSA,
+                crypto.TYPE_RSA: PkDecoratorRSA,
+        }
+        if pk.type() in decorators:
+            return decorators[pk.type()](pk)
+        else:
+            raise UnsupportedPkEncryption("Unsupported private key type %d"
+                                          % pk.type())
+
+
 class UnsupportedPkEncryption(Exception):
     '''
     When we encounter unsupported encryption algorithms
@@ -438,6 +502,8 @@ def main():
             if not args.check:
                 logging.info('Print RSA private keys')
                 for rsa_object in rsa_objects:
+                    if args.informational:
+                        print(PkDecoratorFactory.create(rsa_object))
                     print(rsa_object.to_cryptography_key().private_bytes(
                         encoding=serialization.Encoding.PEM,
                         format=serialization.PrivateFormat.TraditionalOpenSSL,
@@ -448,6 +514,8 @@ def main():
             if not args.check:
                 logging.info('Print private keys')
                 for pk_object in pk_objects:
+                    if args.informational:
+                        print(PkDecoratorFactory.create(pk_object))
                     print(crypto.dump_privatekey(crypto.FILETYPE_PEM,
                                                  pk_object).decode('ascii'),
                           end='')