diff --git a/rankcalc.py b/rankcalc.py
new file mode 100755
index 0000000..726ee72
--- /dev/null
+++ b/rankcalc.py
@@ -0,0 +1,108 @@
+#!/usr/bin/env python
+#
+# Rank-up requirements (EXP) calculator
+
+import os
+import sys
+import getopt
+from math import floor
+
+# algorithm from: http://decaf.kouhi.me/lovelive/index.php?title=Gameplay#Ranks
+def calc(game_version, starting_rank, starting_exp, desired_rank):
+    required_exp = 0
+    for rank in range(starting_rank, desired_rank):
+        required_exp_for_next_rank = round(34.45 * rank - 551)
+        # account for half EXP on JP (only if rank < 100)
+        if game_version == "JP" and rank < 100:
+            required_exp_for_next_rank = required_exp_for_next_rank // 2
+        #print "AT RANK %d NEED %d EXP" % (rank, required_exp_for_next_rank)
+        required_exp = required_exp + required_exp_for_next_rank
+    # account for exp we already have
+    required_exp = required_exp - starting_exp
+    print "To get from rank %d (with %d EXP) to rank %d on %s requires %d EXP." % (starting_rank, starting_exp, desired_rank, game_version, required_exp)
+    print "Equivalent to playing the following number of songs of difficulty level:"
+    # round up because you can't play half of a song (although you can play a song half-assedly :P)
+    easy_count = (required_exp // 12) + 1
+    normal_count = (required_exp // 26) + 1
+    hard_count = (required_exp // 46) + 1
+    ex_count = (required_exp // 83) + 1
+    print "EASY (%d)  NORMAL (%d)  HARD (%d)  EXPERT (%d)" % (easy_count, normal_count, hard_count, ex_count)
+    # calc LP
+    LP = 25 + floor(min(desired_rank, 300) / 2) + floor(max(desired_rank - 300, 0) / 3)
+    # calc friend slots
+    friend_slots = 10 + floor(min(desired_rank, 50) / 5) + floor(max(desired_rank - 50, 0) / 10)
+    # print the results
+    print "At rank %d you will have %d LP and %d friend slots." % (desired_rank, LP, friend_slots)
+     
+def usage():
+    print "Usage: %s [options]" % os.path.basename(__file__)
+    print "where [options] can be one or more of:"
+    print "[-H | --help]           Print this help message"
+    print "[-g | --game-version]   Game version (one of: EN, JP, default EN)"
+    print "[-r | --starting-rank]  Starting rank (REQUIRED, must be >= 34)"
+    print "[-e | --starting-exp]   Starting EXP (optional, defaults to 0)"
+    print "[-R | --desired-rank]   Desired rank (REQUIRED, must be >= starting-rank)"
+
+def main(argv):
+    rarity = None
+    game_version = "EN"
+    starting_rank = None
+    desired_rank = None
+    starting_exp = 0
+    try:                                
+        options, remainder = getopt.getopt(argv, "Hg:r:e:R:", ["help", "game-version=", "starting-rank=", "starting-exp=", "desired-rank="])
+    except getopt.GetoptError:
+        usage()
+        sys.exit(2)                     
+    for opt, arg in options:
+        if opt in ('-H', '--help'):
+            usage()
+            sys.exit(0)
+        elif opt in ('-g', '--game-version'):
+            game_version = arg
+        elif opt in ('-r', '--starting-rank'):
+            starting_rank = int(arg)
+        elif opt in ('-e', '--starting-exp'):
+            starting_exp = int(arg)
+        elif opt in ('-R', '--desired-rank'):
+            desired_rank = int(arg)
+
+    # first validate game version
+    # canonicalize it to uppercase
+    game_version = game_version.upper()
+    if game_version != "EN" and game_version != "JP":
+        print "Error: invalid game version (%s)" % game_version
+        usage()
+        sys.exit(1)
+
+    # now validate levels
+    if starting_rank is None:
+        print "Error: must specify starting rank"
+        usage()
+        sys.exit(1)
+    elif desired_rank is None:
+        print "Error: must specify desired rank"
+        usage()
+        sys.exit(1)
+    elif starting_rank < 34:
+        print "Error: starting rank must be greater than or equal to 34"
+        usage()
+        sys.exit(1)
+    elif desired_rank <= starting_rank:
+        print "Error: desired rank must be greater than starting rank"
+        usage()
+        sys.exit(1)
+
+    # now validate starting exp
+    if starting_exp < 0:
+        print "Error: invalid starting EXP (%d)" % starting_exp
+        usage()
+        sys.exit(1)
+        
+    # all is well, go for it
+    calc(game_version, starting_rank, starting_exp, desired_rank)
+
+### main script starts here
+
+if __name__ == "__main__":
+    main(sys.argv[1:])
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