Score Conversion Tables for Commonly Used Tests

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All Wechsler Scales, all Woodcock tests,¹ all Kaufman Tests, Most Tests Published by American Guidance Service, Pro-Ed,² Riverside, the Psychological Corporation, and Many Others

Z-scores (z), Percentile Ranks (PR), Standard Scores (SS) (Mean = 100, s.d. = 15), Scaled Scores (ss) (Mean = 10, s.d. = 3), and Stanines (9)

Z	PR	SS	ss	9	z	PR	SS	ss	9	z	PR	SS	ss	9

+4.00	99.9	160			+1.33	91	120	14	8	-1.40	08	79
+3.93	99.9	159			+1.27	90	119			-1.47	07	78
+3.87	99.9	158			+1.20	88	118			-1.53	06	77		2
+3.80	99.9	157			+1.13	87	117			-1.60	05	76
+3.73	99.9	156			+1.07	86	116			-1.67	05	75	5
+3.67	99.9	155			+1.00	84	115	13	7	-1.73	04	74
+3.60	99.9	154			+0.93	82	114			-1.80	04	73
+3.53	99.9	153			+0.87	81	113			-1.87	03	72
+3.47	99.9	152			+0.80	79	112			-1.93	03	71
+3.40	99.9	151			+0.73	77	111			-2.00	02	70	4
+3.33	99.9	150			+0.67	75	110	12		-2.07	02	69
+3.27	99.9	149			+0.60	73	109			-2.13	02	68
+3.20	99.9	148			+0.53	70	108		6	-2.20	01	67
+3.13	99.9	147			+0.47	68	107			-2.27	01	66
+3.07	99.9	146			+0.40	66	106			-2.33	01	65	3
+3.00	99.9	145	19		+0.33	63	105	11		-2.40	01	64
+2.93	99.8	144			+0.27	61	104			-2.47	01	63
+2.87	99.8	143			+0.20	58	103			-2.53	01	62
+2.80	99.7	142		9	+0.13	55	102			-2.60	0.5	61		1
+2.73	99.7	141			+0.07	53	101			-2.67	0.4	60	2
+2.67	99.6	140	18		0.00	50	100	10	5	-2.73	0.3	59
+2.60	99.5	139			-0.07	47	99			-2.80	0.3	58
+2.53	99	138			-0.13	45	98			-2.87	0.2	57
+2.47	99	137			-0.20	42	97			-2.93	0.2	56
+2.40	99	136			-0.27	39	96			-3.00	0.1	55	1
+2.33	99	135	17		-0.33	37	95	9		-3.07	0.1	54
+2.27	99	134			-0.40	34	94			-3.13	0.1	53
+2.20	99	133			-0.47	32	93		4	-3.20	0.1	52
+2.13	98	132			-0.53	30	92			-3.27	0.1	51
+2.07	98	131			-0.60	27	91			-3.33	0.1	50
+2.00	98	130	16		-0.67	25	90	8		-3.40	0.1	49
+1.93	97	129			-0.73	23	89			-3.47	0.1	48
+1.87	97	128			-0.80	21	88			-3.53	0.1	47
+1.80	96	127			-0.87	19	87			3.60	0.1	46
+1.73	96	126			-0.93	18	86			-3.67	0.1	45
+1.67	95	125	15		-1.00	16	85	7	3	-3.73	0.1	44
+1.60	95	124			-1.07	14	84			-3.80	0.1	43
+1.53	94	123		8	-1.13	13	83			-3.87	0.1	42
+1.47	93	122			-1.20	12	82			-3.93	0.1	41
+1.40	92	121			-1.27	10	81			-4.00	0.1	40
					-1.33	09	80	6	2

1. Tests of which Dr. Woodcock is author or co-author separately compute Standard Scores and Percentile Ranks, so these will not be the precise relationships between Standard Scores and Percentile Ranks.

2. Tests published by Pro-Ed call these Standard Scores “quotients,” and these Scaled Scores “Standard Scores” (which they are, although that is not the common usage).

Differential Ability Scales and Other Tests Using T scores¹

Z-scores (z), Percentile Ranks (PR), Standard Scores (General Conceptual Ability -- GCA) (mean = 100, s.d. = 15), T Scores (T) (mean = 50, s.d. = 10), and Stanines (9)

z	PR	GCA	T	9	z	PR	GCA	T	9	z	PR	GCA	T	9
													36
+4.00	99.9	160	90		+1.33	91	120		8	-1.40	08	79	36
+3.93	99.9	159			+1.27	90	119			-1.47	07	78
+3.87	99.9	158			+1.20	88	118	62		-1.53	06	77		2
+3.80	99.9	157	88		+1.13	87	117			-1.60	05	76	34
+3.73	99.9	156			+1.07	86	116			-1.67	05	75
+3.67	99.9	155			+1.00	84	115	60	7	-1.73	04	74
+3.60	99.9	154	86		+0.93	82	114			-1.80	04	73	32
+3.53	99.9	153			+0.87	81	113			-1.87	03	72
+3.47	99.9	152			+0.80	79	112	58		-1.93	03	71
+3.40	99.9	151	84		+0.73	77	111			-2.00	02	70	30
+3.33	99.9	150			+0.67	75	110			-2.07	02	69
+3.27	99.9	149			+0.60	73	109	56		-2.13	02	68
+3.20	99.9	148	82		+0.53	70	108		6	-2.20	01	67	28
+3.13	99.9	147			+0.47	68	107			-2.27	01	66
+3.07	99.9	146			+0.40	66	106	54		-2.33	01	65
+3.00	99.9	145	80		+0.33	63	105			-2.40	01	64	26
+2.93	99.8	144			+0.27	61	104			-2.47	01	63
+2.87	99.8	143			+0.20	58	103	52		-2.53	01	62
+2.80	99.7	142	78	9	+0.13	55	102			-2.60	0.5	61	24	1
+2.73	99.7	141			+0.07	53	101			-2.67	0.4	60
+2.67	99.6	140			0.00	50	100	50	5	-2.73	0.3	59
+2.60	99.5	139	76		-0.07	47	99			-2.80	0.3	58	22
+2.53	99	138			-0.13	45	98			-2.87	0.2	57
+2.47	99	137			-0.20	42	97	48		-2.93	0.2	56
+2.40	99	136	74		-0.27	39	96			-3.00	0.1	55	20
+2.33	99	135			-0.33	37	95			-3.07	0.1	54
+2.27	99	134			-0.40	34	94	46		-3.13	0.1	53
+2.20	99	133	72		-0.47	32	93		4	-3.20	0.1	52	18
+2.13	98	132			-0.53	30	92			-3.27	0.1	51
+2.07	98	131			-0.60	27	91	44		-3.33	0.1	50
+2.00	98	130	70		-0.67	25	90			-3.40	0.1	49	16
+1.93	97	129			-0.73	23	89			-3.47	0.1	48
+1.87	97	128			-0.80	21	88	42		-3.53	0.1	47
+1.80	96	127	68		-0.87	19	87			3.60	0.1	46	14
+1.73	96	126			-0.93	18	86			-3.67	0.1	45
+1.67	95	125			-1.00	16	85	40	3	-3.73	0.1	44
+1.60	95	124	66		-1.07	14	84			-3.80	0.1	43	12
+1.53	94	123		8	-1.13	13	83			-3.87	0.1	42
+1.47	93	122			-1.20	12	82	38		-3.93	0.1	41
+1.40	92	121	64		-1.27	10	81			-4.00	0.1	40	10
					-1.33	09	80		2

1. Odd-numbered T scores fall between Standard Scores. For instance, a T score of 49 is equivalent to a z-score of -0.10, and a standard score of 98.5

Stanford-Binet Intelligence Scale, 4^th ed. and Other Tests Using Standard Scores with a Mean of 100 and SD 16

Z-scores (z), Percentile Ranks (PR), Composite and Area Standard Scores (SAS[1]) (Mean = 100 s.d. = 16), Subtest Standard Scores (sas) (Mean = 50, s.d. = 8), and Stanines (9)

Z	PR	SAS	sas	9	z	PR	SAS	sas	9	z	PR	SAS	sas	9

+4.00	99.9	164	82		+1.31	91	121	61	8	-1.38	08	78	39
+3.94	99.9	163	82		+1.25	89	120	60		-1.44	08	77	39	2
+3.88	99.9	162	81		+1.19	88	119	60		-1.50	07	76	38
+3.81	99.9	161	81		+1.13	87	118	59		-1.56	06	75	38
+3.75	99.9	160	80		+1.06	86	117	59		-1.63	05	74	37
+3.69	99.9	159	80		+1.00	84	116	58	7	-1.69	05	73	37
+3.63	99.9	158	79		+0.94	83	115	58		-1.75	04	72	36
+3.56	99.9	157	79		+0.88	81	114	57		-1.81	04	71	36
+3.50	99.9	156	78		+0.81	79	113	57		-1.88	03	70	35
+3.44	99.9	155	78		+0.75	77	112	56		-1.94	03	69	35
+3.38	99.9	154	77		+0.69	75	111	56		-2.00	02	68	34
+3.31	99.9	153	77		+0.63	73	110	55		-2.06	02	67	34
+3.25	99.9	152	76		+0.56	71	109	55		-2.13	02	66	33
+3.19	99.9	151	76		+0.50	69	108	54	6	-2.19	01	65	33
+3.13	99.9	150	75		+0.44	67	107	54		-2.25	01	64	32
+3.06	99.9	149	75	9	+0.38	65	106	53		-2.31	01	63	32
+3.00	99.9	148	74		+0.31	62	105	53		-2.38	01	62	31
+2.94	99.8	147	74		+0.25	60	104	52		-2.44	01	61	31
+2.88	99.8	146	73		+0.19	57	103	52		-2.50	01	60	30
+2.81	99.8	145	73		+0.13	55	102	51		-2.53	01	59	30
+2.75	99.7	144	72		+0.06	52	101	51		-2.63	0.4	58	29
+2.69	99.6	143	72		0.00	50	100	50	5	-2.69	0.4	57	29
+2.63	99.6	142	71		-0.06	48	99	50		-2.75	0.3	56	28
+2.56	99	141	71		-0.13	45	98	49		-2.81	0.3	55	28	1
+2.50	99	140	70		-0.19	43	97	49		-2.88	0.2	54	27
+2.44	99	139	70		-0.25	40	96	48		-2.94	0.2	53	27
+2.38	99	138	69		-0.31	38	95	48		-3.00	0.1	52	26
+2.31	99	137	69		-0.38	35	94	47		-3.06	0.1	51	26
+2.25	99	136	68		-0.44	33	93	47	4	-3.13	0.1	50	25
+2.19	99	135	68		-0.50	31	92	46		-3.19	0.1	49	25
+2.13	98	134	67		-0.56	29	91	46		-3.25	0.1	48	24
+2.06	98	133	67		-0.63	27	90	45		-3.31	0.1	47	24
+2.00	98	132	66		-0.69	25	89	45		-3.38	0.1	46	23
+1.94	97	131	66		-0.75	23	88	44		-3.44	0.1	45	23
+1.88	97	130	65		-0.81	21	87	44		-3.50	0.1	44	22
+1.81	96	129	65		-0.88	19	86	43		-3.56	0.1	43	22
+1.75	96	128	64		-0.94	17	85	43	3	-3.63	0.1	42	21
+1.69	95	127	64		-1.00	16	84	42		-3.69	0.1	41	21
+1.63	95	126	63		-1.06	14	83	42		-3.75	0.1	40	20
+1.56	94	125	63		-1.13	13	82	41		-3.81	0.4	39	20
+1.50	93	124	62	8	-1.19	12	81	41		-3.88	0.1	38	19
+1.44	92	123	62		-1.25	11	80	40