How VA Math Works

VA doesn’t add disability ratings together. It combines them with the “whole person” method in 38 CFR 4.25, adds a bilateral factor for paired arms or legs under 38 CFR 4.26, and rounds to the nearest 10% only at the end. Here is the exact method our calculator uses.

Sources: 38 CFR 4.25 Combined ratings table and 38 CFR 4.26 Bilateral factor (eCFR), retrieved October 19, 2026.

Step 1: Sort ratings from most to least severe

Per 38 CFR 4.25(a), “the disabilities will first be arranged in the exact order of their severity, beginning with the greatest disability.”

Step 2: Combine one rating at a time

Think of efficiency. In the regulation’s own words, a person with a 60% disability is 40% efficient. A further 30% disability leaves 70% of that 40%, or 28% efficiency, so the person is 72% disabled. As a formula, each step is:

combined = current + next × (100 − current) ÷ 100, rounded to the nearest whole number

This reproduces every value in VA’s Combined Ratings Table (Table I). We checked all 684 cells automatically.

Step 3: Round to the nearest 10, once

The final combined value is “converted to the nearest number divisible by 10, and combined values ending in 5 will be adjusted upward” (4.25(a)). This happens “only once per rating decision” and is “the last procedure” (4.25(b)). So 65 becomes 70%, and 64 becomes 60%.

The bilateral factor (38 CFR 4.26)

If you have partial disability in both arms, both legs, or paired skeletal muscles, VA combines the left and right ratings as usual and then adds (doesn’t combine) 10% of that value. The result counts as one disability when sorting and combining with the rest.

Arms and legs as a whole. A rating for the right thigh and one for the left foot still count as paired legs (4.26(a)).
All four limbs. If both arms and both legs are affected, all of those ratings are combined together, then 10% is added (4.26(b)).
Must be compensable on each side. Each side needs a rating of at least 10% (4.26(c)).
Most favorable result. If leaving some bilateral ratings out of the factor gives a higher combined rating, VA does that instead (4.26(d)). Our calculator tests every option and keeps the best one.

How the bilateral value is rounded: the regulation’s example turns 10% + 10% (19) into 21. That means 19 + 1.9 = 20.9, rounded to the nearest whole number. Our calculator follows that example.

Worked examples (these are our unit tests)

Two ratings: 50% and 30%

Example from 38 CFR 4.25(a).

Order by severity: 50, 30.
50 combined with 30: 50 + 30 × 50% = 65 → 65
Combined value 65 rounds to the nearest 10: 70%.

Two ratings: 40% and 20%

Example from 38 CFR 4.25(a).

Order by severity: 40, 20.
40 combined with 20: 40 + 20 × 60% = 52 → 52
Combined value 52 rounds to the nearest 10: 50%.

Three ratings: 60%, 40% and 20%

Example from 38 CFR 4.25(a).

Order by severity: 60, 40, 20.
60 combined with 40: 60 + 40 × 40% = 76 → 76
76 combined with 20: 76 + 20 × 24% = 80.8 → 81
Combined value 81 rounds to the nearest 10: 80%.

Bilateral: 60%, 20%, and 10% on each leg

Example from 38 CFR 4.26.

Bilateral group (10% left leg, 10% right leg) combines to 19. Add 10% of that (1.9): 19 + 1.9 = 21 after rounding to a whole number. Treat 21 as one disability.
Order by severity: 60, 21, 20.
60 combined with 21: 60 + 21 × 40% = 68.4 → 68
68 combined with 20: 68 + 20 × 32% = 74.4 → 74
Combined value 74 rounds to the nearest 10: 70%.

Four ratings of 20%

Shows why VA rounds only once, at the end.

Order by severity: 20, 20, 20, 20.
20 combined with 20: 20 + 20 × 80% = 36 → 36
36 combined with 20: 36 + 20 × 64% = 48.8 → 49
49 combined with 20: 49 + 20 × 51% = 59.2 → 59
Combined value 59 rounds to the nearest 10: 60%.

From rating to pay

Once you have a rounded rating, VA’s rate table gives the monthly amount for your dependent status. At 10% and 20%, VA pays no extra for dependents. See the 2026 pay chart.

How we count children: VA’s “with 1 child” rate already includes one child. Each additional child under 18 adds the “additional child” amount, and each child 18–23 in a qualifying school program adds the school-child amount. This matches VA.gov’s own worked examples. If you have only school-age children (none under 18), we use the no-child basic rate and add the school-child amount for each one, because the school-child rate is paid instead of the regular child rate. Check your VA award letter to confirm how VA counted your dependents.

Full Combined Ratings Table (Table I)

Show the full 38 CFR 4.25 Table I

Find your current combined value in the left column and the next rating along the top. The number where they meet is the new combined value.

38 CFR 4.25 Table I — Combined Ratings Table (10 combined with 10 is 19)
Combined so far	10	20	30	40	50	60	70	80	90
19	27	35	43	51	60	68	76	84	92
20	28	36	44	52	60	68	76	84	92
21	29	37	45	53	61	68	76	84	92
22	30	38	45	53	61	69	77	84	92
23	31	38	46	54	62	69	77	85	92
24	32	39	47	54	62	70	77	85	92
25	33	40	48	55	63	70	78	85	93
26	33	41	48	56	63	70	78	85	93
27	34	42	49	56	64	71	78	85	93
28	35	42	50	57	64	71	78	86	93
29	36	43	50	57	65	72	79	86	93
30	37	44	51	58	65	72	79	86	93
31	38	45	52	59	66	72	79	86	93
32	39	46	52	59	66	73	80	86	93
33	40	46	53	60	67	73	80	87	93
34	41	47	54	60	67	74	80	87	93
35	42	48	55	61	68	74	81	87	94
36	42	49	55	62	68	74	81	87	94
37	43	50	56	62	69	75	81	87	94
38	44	50	57	63	69	75	81	88	94
39	45	51	57	63	70	76	82	88	94
40	46	52	58	64	70	76	82	88	94
41	47	53	59	65	71	76	82	88	94
42	48	54	59	65	71	77	83	88	94
43	49	54	60	66	72	77	83	89	94
44	50	55	61	66	72	78	83	89	94
45	51	56	62	67	73	78	84	89	95
46	51	57	62	68	73	78	84	89	95
47	52	58	63	68	74	79	84	89	95
48	53	58	64	69	74	79	84	90	95
49	54	59	64	69	75	80	85	90	95
50	55	60	65	70	75	80	85	90	95
51	56	61	66	71	76	80	85	90	95
52	57	62	66	71	76	81	86	90	95
53	58	62	67	72	77	81	86	91	95
54	59	63	68	72	77	82	86	91	95
55	60	64	69	73	78	82	87	91	96
56	60	65	69	74	78	82	87	91	96
57	61	66	70	74	79	83	87	91	96
58	62	66	71	75	79	83	87	92	96
59	63	67	71	75	80	84	88	92	96
60	64	68	72	76	80	84	88	92	96
61	65	69	73	77	81	84	88	92	96
62	66	70	73	77	81	85	89	92	96
63	67	70	74	78	82	85	89	93	96
64	68	71	75	78	82	86	89	93	96
65	69	72	76	79	83	86	90	93	97
66	69	73	76	80	83	86	90	93	97
67	70	74	77	80	84	87	90	93	97
68	71	74	78	81	84	87	90	94	97
69	72	75	78	81	85	88	91	94	97
70	73	76	79	82	85	88	91	94	97
71	74	77	80	83	86	88	91	94	97
72	75	78	80	83	86	89	92	94	97
73	76	78	81	84	87	89	92	95	97
74	77	79	82	84	87	90	92	95	97
75	78	80	83	85	88	90	93	95	98
76	78	81	83	86	88	90	93	95	98
77	79	82	84	86	89	91	93	95	98
78	80	82	85	87	89	91	93	96	98
79	81	83	85	87	90	92	94	96	98
80	82	84	86	88	90	92	94	96	98
81	83	85	87	89	91	92	94	96	98
82	84	86	87	89	91	93	95	96	98
83	85	86	88	90	92	93	95	97	98
84	86	87	89	90	92	94	95	97	98
85	87	88	90	91	93	94	96	97	99
86	87	89	90	92	93	94	96	97	99
87	88	90	91	92	94	95	96	97	99
88	89	90	92	93	94	95	96	98	99
89	90	91	92	93	95	96	97	98	99
90	91	92	93	94	95	96	97	98	99
91	92	93	94	95	96	96	97	98	99
92	93	94	94	95	96	97	98	98	99
93	94	94	95	96	97	97	98	99	99
94	95	95	96	96	97	98	98	99	99

Source: eCFR, 38 CFR 4.25, retrieved October 19, 2026. Our calculator reproduces every one of these 684 values exactly (verified by automated tests).

Frequently asked questions

Why is 50% + 30% equal to 70% and not 80%?

VA treats you as 100% “efficient” to start. A 50% rating leaves 50% efficiency. A 30% rating then takes 30% of that remaining 50%, which is 15 points. 50 + 15 = 65, and 65 rounds up to 70%.

Does VA round at each step?

Each step uses a whole number from the Combined Ratings Table, but rounding to the nearest 10 happens only once, at the very end (38 CFR 4.25(b)).

Does the bilateral factor apply to one arm and one leg?

No. Under 38 CFR 4.26 it applies to both arms, both legs, or paired skeletal muscles, and each side must have a compensable (10% or higher) rating.

Combined so far	10	20	30	40	50	60	70	80	90
19	27	35	43	51	60	68	76	84	92
20	28	36	44	52	60	68	76	84	92
21	29	37	45	53	61	68	76	84	92
22	30	38	45	53	61	69	77	84	92
23	31	38	46	54	62	69	77	85	92
24	32	39	47	54	62	70	77	85	92
25	33	40	48	55	63	70	78	85	93
26	33	41	48	56	63	70	78	85	93
27	34	42	49	56	64	71	78	85	93
28	35	42	50	57	64	71	78	86	93
29	36	43	50	57	65	72	79	86	93
30	37	44	51	58	65	72	79	86	93
31	38	45	52	59	66	72	79	86	93
32	39	46	52	59	66	73	80	86	93
33	40	46	53	60	67	73	80	87	93
34	41	47	54	60	67	74	80	87	93
35	42	48	55	61	68	74	81	87	94
36	42	49	55	62	68	74	81	87	94
37	43	50	56	62	69	75	81	87	94
38	44	50	57	63	69	75	81	88	94
39	45	51	57	63	70	76	82	88	94
40	46	52	58	64	70	76	82	88	94
41	47	53	59	65	71	76	82	88	94
42	48	54	59	65	71	77	83	88	94
43	49	54	60	66	72	77	83	89	94
44	50	55	61	66	72	78	83	89	94
45	51	56	62	67	73	78	84	89	95
46	51	57	62	68	73	78	84	89	95
47	52	58	63	68	74	79	84	89	95
48	53	58	64	69	74	79	84	90	95
49	54	59	64	69	75	80	85	90	95
50	55	60	65	70	75	80	85	90	95
51	56	61	66	71	76	80	85	90	95
52	57	62	66	71	76	81	86	90	95
53	58	62	67	72	77	81	86	91	95
54	59	63	68	72	77	82	86	91	95
55	60	64	69	73	78	82	87	91	96
56	60	65	69	74	78	82	87	91	96
57	61	66	70	74	79	83	87	91	96
58	62	66	71	75	79	83	87	92	96
59	63	67	71	75	80	84	88	92	96
60	64	68	72	76	80	84	88	92	96
61	65	69	73	77	81	84	88	92	96
62	66	70	73	77	81	85	89	92	96
63	67	70	74	78	82	85	89	93	96
64	68	71	75	78	82	86	89	93	96
65	69	72	76	79	83	86	90	93	97
66	69	73	76	80	83	86	90	93	97
67	70	74	77	80	84	87	90	93	97
68	71	74	78	81	84	87	90	94	97
69	72	75	78	81	85	88	91	94	97
70	73	76	79	82	85	88	91	94	97
71	74	77	80	83	86	88	91	94	97
72	75	78	80	83	86	89	92	94	97
73	76	78	81	84	87	89	92	95	97
74	77	79	82	84	87	90	92	95	97
75	78	80	83	85	88	90	93	95	98
76	78	81	83	86	88	90	93	95	98
77	79	82	84	86	89	91	93	95	98
78	80	82	85	87	89	91	93	96	98
79	81	83	85	87	90	92	94	96	98
80	82	84	86	88	90	92	94	96	98
81	83	85	87	89	91	92	94	96	98
82	84	86	87	89	91	93	95	96	98
83	85	86	88	90	92	93	95	97	98
84	86	87	89	90	92	94	95	97	98
85	87	88	90	91	93	94	96	97	99
86	87	89	90	92	93	94	96	97	99
87	88	90	91	92	94	95	96	97	99
88	89	90	92	93	94	95	96	98	99
89	90	91	92	93	95	96	97	98	99
90	91	92	93	94	95	96	97	98	99
91	92	93	94	95	96	96	97	98	99
92	93	94	94	95	96	97	98	98	99
93	94	94	95	96	97	97	98	99	99
94	95	95	96	96	97	98	98	99	99

Combined so far	10	20	30	40	50	60	70	80	90
19	27	35	43	51	60	68	76	84	92
20	28	36	44	52	60	68	76	84	92
21	29	37	45	53	61	68	76	84	92
22	30	38	45	53	61	69	77	84	92
23	31	38	46	54	62	69	77	85	92
24	32	39	47	54	62	70	77	85	92
25	33	40	48	55	63	70	78	85	93
26	33	41	48	56	63	70	78	85	93
27	34	42	49	56	64	71	78	85	93
28	35	42	50	57	64	71	78	86	93
29	36	43	50	57	65	72	79	86	93
30	37	44	51	58	65	72	79	86	93
31	38	45	52	59	66	72	79	86	93
32	39	46	52	59	66	73	80	86	93
33	40	46	53	60	67	73	80	87	93
34	41	47	54	60	67	74	80	87	93
35	42	48	55	61	68	74	81	87	94
36	42	49	55	62	68	74	81	87	94
37	43	50	56	62	69	75	81	87	94
38	44	50	57	63	69	75	81	88	94
39	45	51	57	63	70	76	82	88	94
40	46	52	58	64	70	76	82	88	94
41	47	53	59	65	71	76	82	88	94
42	48	54	59	65	71	77	83	88	94
43	49	54	60	66	72	77	83	89	94
44	50	55	61	66	72	78	83	89	94
45	51	56	62	67	73	78	84	89	95
46	51	57	62	68	73	78	84	89	95
47	52	58	63	68	74	79	84	89	95
48	53	58	64	69	74	79	84	90	95
49	54	59	64	69	75	80	85	90	95
50	55	60	65	70	75	80	85	90	95
51	56	61	66	71	76	80	85	90	95
52	57	62	66	71	76	81	86	90	95
53	58	62	67	72	77	81	86	91	95
54	59	63	68	72	77	82	86	91	95
55	60	64	69	73	78	82	87	91	96
56	60	65	69	74	78	82	87	91	96
57	61	66	70	74	79	83	87	91	96
58	62	66	71	75	79	83	87	92	96
59	63	67	71	75	80	84	88	92	96
60	64	68	72	76	80	84	88	92	96
61	65	69	73	77	81	84	88	92	96
62	66	70	73	77	81	85	89	92	96
63	67	70	74	78	82	85	89	93	96
64	68	71	75	78	82	86	89	93	96
65	69	72	76	79	83	86	90	93	97
66	69	73	76	80	83	86	90	93	97
67	70	74	77	80	84	87	90	93	97
68	71	74	78	81	84	87	90	94	97
69	72	75	78	81	85	88	91	94	97
70	73	76	79	82	85	88	91	94	97
71	74	77	80	83	86	88	91	94	97
72	75	78	80	83	86	89	92	94	97
73	76	78	81	84	87	89	92	95	97
74	77	79	82	84	87	90	92	95	97
75	78	80	83	85	88	90	93	95	98
76	78	81	83	86	88	90	93	95	98
77	79	82	84	86	89	91	93	95	98
78	80	82	85	87	89	91	93	96	98
79	81	83	85	87	90	92	94	96	98
80	82	84	86	88	90	92	94	96	98
81	83	85	87	89	91	92	94	96	98
82	84	86	87	89	91	93	95	96	98
83	85	86	88	90	92	93	95	97	98
84	86	87	89	90	92	94	95	97	98
85	87	88	90	91	93	94	96	97	99
86	87	89	90	92	93	94	96	97	99
87	88	90	91	92	94	95	96	97	99
88	89	90	92	93	94	95	96	98	99
89	90	91	92	93	95	96	97	98	99
90	91	92	93	94	95	96	97	98	99
91	92	93	94	95	96	96	97	98	99
92	93	94	94	95	96	97	98	98	99
93	94	94	95	96	97	97	98	99	99
94	95	95	96	96	97	98	98	99	99

Combined so far	10	20	30	40	50	60	70	80	90
19	27	35	43	51	60	68	76	84	92
20	28	36	44	52	60	68	76	84	92
21	29	37	45	53	61	68	76	84	92
22	30	38	45	53	61	69	77	84	92
23	31	38	46	54	62	69	77	85	92
24	32	39	47	54	62	70	77	85	92
25	33	40	48	55	63	70	78	85	93
26	33	41	48	56	63	70	78	85	93
27	34	42	49	56	64	71	78	85	93
28	35	42	50	57	64	71	78	86	93
29	36	43	50	57	65	72	79	86	93
30	37	44	51	58	65	72	79	86	93
31	38	45	52	59	66	72	79	86	93
32	39	46	52	59	66	73	80	86	93
33	40	46	53	60	67	73	80	87	93
34	41	47	54	60	67	74	80	87	93
35	42	48	55	61	68	74	81	87	94
36	42	49	55	62	68	74	81	87	94
37	43	50	56	62	69	75	81	87	94
38	44	50	57	63	69	75	81	88	94
39	45	51	57	63	70	76	82	88	94
40	46	52	58	64	70	76	82	88	94
41	47	53	59	65	71	76	82	88	94
42	48	54	59	65	71	77	83	88	94
43	49	54	60	66	72	77	83	89	94
44	50	55	61	66	72	78	83	89	94
45	51	56	62	67	73	78	84	89	95
46	51	57	62	68	73	78	84	89	95
47	52	58	63	68	74	79	84	89	95
48	53	58	64	69	74	79	84	90	95
49	54	59	64	69	75	80	85	90	95
50	55	60	65	70	75	80	85	90	95
51	56	61	66	71	76	80	85	90	95
52	57	62	66	71	76	81	86	90	95
53	58	62	67	72	77	81	86	91	95
54	59	63	68	72	77	82	86	91	95
55	60	64	69	73	78	82	87	91	96
56	60	65	69	74	78	82	87	91	96
57	61	66	70	74	79	83	87	91	96
58	62	66	71	75	79	83	87	92	96
59	63	67	71	75	80	84	88	92	96
60	64	68	72	76	80	84	88	92	96
61	65	69	73	77	81	84	88	92	96
62	66	70	73	77	81	85	89	92	96
63	67	70	74	78	82	85	89	93	96
64	68	71	75	78	82	86	89	93	96
65	69	72	76	79	83	86	90	93	97
66	69	73	76	80	83	86	90	93	97
67	70	74	77	80	84	87	90	93	97
68	71	74	78	81	84	87	90	94	97
69	72	75	78	81	85	88	91	94	97
70	73	76	79	82	85	88	91	94	97
71	74	77	80	83	86	88	91	94	97
72	75	78	80	83	86	89	92	94	97
73	76	78	81	84	87	89	92	95	97
74	77	79	82	84	87	90	92	95	97
75	78	80	83	85	88	90	93	95	98
76	78	81	83	86	88	90	93	95	98
77	79	82	84	86	89	91	93	95	98
78	80	82	85	87	89	91	93	96	98
79	81	83	85	87	90	92	94	96	98
80	82	84	86	88	90	92	94	96	98
81	83	85	87	89	91	92	94	96	98
82	84	86	87	89	91	93	95	96	98
83	85	86	88	90	92	93	95	97	98
84	86	87	89	90	92	94	95	97	98
85	87	88	90	91	93	94	96	97	99
86	87	89	90	92	93	94	96	97	99
87	88	90	91	92	94	95	96	97	99
88	89	90	92	93	94	95	96	98	99
89	90	91	92	93	95	96	97	98	99
90	91	92	93	94	95	96	97	98	99
91	92	93	94	95	96	96	97	98	99
92	93	94	94	95	96	97	98	98	99
93	94	94	95	96	97	97	98	99	99
94	95	95	96	96	97	98	98	99	99