diff --git a/bin/create_designid_status_replace_designs.py b/bin/create_designid_status_replace_designs.py
index 401301a..61e01a1 100644
--- a/bin/create_designid_status_replace_designs.py
+++ b/bin/create_designid_status_replace_designs.py
@@ -4,7 +4,9 @@
 import numpy as np
 import glob
 import datetime
-from tqdm import trange
+from tqdm import trange, tqdm
+from multiprocessing import Pool
+from functools import partial
 
 from astropy.io import fits
 from astropy.table import Table
@@ -16,7 +18,7 @@
 from sdssdb.peewee.sdss5db import targetdb
 
 
-def get_designid_status(file, field_id):
+def get_designid_status(file, field_id, Ncores):
     """
     get the designid_status for a manual design
     """
@@ -24,17 +26,24 @@ def get_designid_status(file, field_id):
     from mugatu.designmode import find_designid_status
     from mugatu.designs_to_targetdb import assignment_hash
 
-    def designid_status(design_file, obsTime, exp, field_id):
+    def create_des_object(design_file, obsTime, exp):
         des = FPSDesign(design_pk=-1,
                         obsTime=obsTime,
                         design_file=design_file,
                         manual_design=True,
                         exp=exp)
         des.build_design_manual()
+        return des
+
+    def designid_status(design_file, obsTime, exp, fexp, field_id, des_objs=None):
+        if des_objs is None:
+            des = create_des_object(design_file, obsTime, exp)
+        else:
+            des = des_objs[fexp]
 
         assign_hash = assignment_hash(des.design['catalogID'][des.design['robotID'] != -1],
                                       des.design['holeID'][des.design['robotID'] != -1])
-        designid_status = find_designid_status(field_id, exp, assign_hash=assign_hash)
+        designid_status = find_designid_status(field_id, fexp, assign_hash=assign_hash)
         return designid_status
 
     with fits.open(file) as hdu:
@@ -56,10 +65,20 @@ def designid_status(design_file, obsTime, exp, field_id):
     status = np.zeros(n_exp, dtype='S20')
     if n_exp == 1:
         exp = 0
-        designid[exp], status[exp] = designid_status(file, obsTime, exp, field_id)
+        designid[exp], status[exp] = designid_status(file, obsTime, exp, exp, field_id)
     else:
+        if Ncores > 1:
+            with Pool(processes=Ncores) as pool:
+                des_objs = tqdm(pool.imap(partial(create_des_object, design_file=file,
+                                                  obsTime=obsTime),
+                                                  range(1, n_exp + 1)),
+                                          total=len(n_exp))
+                des_objs = [r for r in des_objs]
+        else:
+            des_objs = None
         for exp in trange(n_exp):
-            designid[exp], status[exp] = designid_status(file, obsTime, exp + 1, field_id)
+            designid[exp], status[exp] = designid_status(file, obsTime, exp + 1, exp,
+                                                         field_id, des_objs=des_objs)
     return designid, status
 
 
@@ -76,11 +95,15 @@ def designid_status(design_file, obsTime, exp, field_id):
     parser.add_argument('-f', '--fieldids', dest='fieldids', nargs='+',
                         help='field_ids to replace)',
                         type=int, required=True)
+    parser.add_argument('-n', '--Ncores', dest='Ncores',
+                        type=int, help='number of cores to use. If Ncores=1, then not run in parallal.',
+                        default=1, nargs='?')
 
     args = parser.parse_args()
     loc = args.loc
     plan = args.plan
     fieldids = args.fieldids
+    Ncores = args.Ncores
 
     if loc == 'local':
         targetdb.database.connect_from_parameters(user='sdss',
@@ -122,7 +145,7 @@ def designid_status(design_file, obsTime, exp, field_id):
                                                        targetdb.Field.field_id >= 100000)
             if len(same_field) > 0:
                 field_id = same_field[0].field_id
-                designid, status = get_designid_status(file, field_id)
+                designid, status = get_designid_status(file, field_id, Ncores)
             else:
                 field_id = -1
                 designid = np.zeros(n_exp, dtype='>i4') - 1