As of 2013, with 30 NBA teams, 16 qualify for the playoffs and the remaining 14 teams are entered in the draft lottery. These 14 teams are ranked in reverse order of their regular season record and are assigned the following number of chances
250 combinations, 25.0% chance of receiving the #1 pick
199 combinations, 19.9% chance
156 combinations, 15.6% chance
119 combinations, 11.9% chance
88 combinations, 8.8% chance
63 combinations, 6.3% chance
43 combinations, 4.3% chance
28 combinations, 2.8% chance
17 combinations, 1.7% chance
11 combinations, 1.1% chance
8 combinations, 0.8% chance
7 combinations, 0.7% chance
6 combinations, 0.6% chance
5 combinations, 0.5% chance
Here are the odds for each seed to get specific picks if there were no ties (rounded to 3 decimal places):
Seed Chances 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th
1 250 .250 .215 .178 .357
2 199 .199 .188 .171 .319 .123
3 156 .156 .157 .156 .226 .265 .040
4 119 .119 .126 .133 .099 .351 .160 .012
5 88 .088 .097 .107 .261 .360 .084 .004
6 63 .063 .071 .081 .439 .305 .040 .001
7 43 .043 .049 .058 .599 .232 .018 .000
8 28 .028 .033 .039 .724 .168 .008 .000
9 17 .017 .020 .024 .813 .122 .004 .000
10 11 .011 .013 .016 .870 .089 .002 .000
11 8 .008 .009 .012 .907 .063 .001 .000
12 7 .007 .008 .010 .935 .039 .000
13 6 .006 .007 .009 .960 .018
14 5 .005 .006 .007 .982
In the event that teams finish with the same record, each tied team receives the average of the total number of combinations for the positions that they occupy. In 2007, the Minnesota Timberwolves and the Portland Trail Blazers tied for the sixth worst record. The average of the 6th and 7th positions in the lottery was taken, resulting in each team getting 53 combinations (the average of 63 and 43). Should the average number not be an integer, a coin flip is then used to determine which team or teams receive the extra combination(s). The result of the coin flip is also used to determine who receives the earlier pick in the event that neither of the tied teams wins one of the first three picks via the lottery.