Hit Points per Die

Weight (lbs)	Dice Rolled	Range	Average H.P. per HD
up to 10	d2	1-2	1.5
11-30	d3	1-3	2
31-70	d4	1-4	2.5
71-150	d6	1-6	3.5
151-290	d8	1-8	4.5
291-510	2d4	2-8	5
511-830	d10	1-10	5.5
831-1,275	d4+d6	2-10	6
1,276-1,800	d12	1-12	6.5
1,801-2,500	2d6	2-12	7
2,501-3,500	3d4	3-12	7.5
3,501-4,800	d6+d8	2-14	8
4,801-6,500	2d4+d6	3-14	8.5
6,501-8,700	2d8	2-16	9
8,701-11,500	d4+2d6	3-16	9.5
11,501-15,000	d8+d10	2-18	10
15,000-19,000	2d10	2-20	11
19,001-24,000	d10+d12	2-22	12
24,001-31,000	2d12	2-24	13
31,001-40,000	2d8+d10	3-26	14.5
40,001-51,000	d8+2d10	3-28	15.5
51,001-65,000	3d10	3-30	16.5
65,001-82,000	4d8	4-32	18
82,000-100,000	3d12	3-36	19.5
100,001-120,000	d8+3d10	4-38	21
120,001-150,000	3d10+d12	3-42	23
150,001-190,000	d10+3d12	4-46	25
190,001-240,000	5d10	5-50	27.5
240,001-300,000	3d8+3d10	6-54	30
300,001-380,000	6d10	6-60	33
380,001-480,000	3d10+3d12	6-66	36
480,001 or more	6d10+d12	7-72	39.5

For the purposes of determining a creature's hit points, a distinction is made between the creature's hit dice (HD), which indicates the creature's ability to hit, and the creature's mass, which can vary greatly with respect to HD. For example, a cockatrice has 5 HD and weighs 98 lbs., while a moose also has 5 HD and weighs 1,220 lbs., or more. Therefore, because of its mass, and although a cockatrice is still a dangerous creature, a moose will have more hit points than a cockatrice.

How much more is indicated by the table shown. The dice rolled indicate the creature's hit points per die. For example, the moose described above would have 5d4+5d6 hit points, or 10-50 (average 30). Comparatively, the cockatrice would have 5d6 hit points, or 5-30 (average 17.5). The adjustment for hit point per die is staggered so that as the creature increases in mass, the hit points gained are progressively less per pound. This reflects the amount of comparatively wasted mass of large creatures compared to their fighting ability.

Mass plus Character Level

The table is also used to indicate the number of hit points that player and non-player characters possess due to their weight, which is added to the hit points they gain from experience levels. For example, a human 1st level fighter normally gains 1d10 hit points from their character class, adjusted by constitution. Humans and other player character races possess either 1 or 1+1 hit dice, which adds hit points to their total according to the table shown.

For example, Piotr the elven 1st level Thief receives 1d6 hit points from his character class (a player character would automatically start with the maximum, "6"), which is adjusted by +1 due to his 15 constitution; he also receives 1d6 from his mass, 100 lbs.; and, as elves have a natural HD of 1+1, which is also considered his mass, he receives an additional +1 bonus. In total, this makes his average starting hit points equal to 9 (a player character would have an average starting hit points of 11).

See Also,
Combat
Negative Hit Points