ECG Normal Values

About These Reference Values

The normal ranges of electrocardiographic interval values are poorly understood. The purpose of this page is to provide a reliable set of normal values for use in research and education. These values are published.

Due to lack of large enough datasets derived from diverse demographics, previous normal ranges for the ECG have inadequately or inaccurately accounted for the large variations of normal based upon age and sex. The tables accessible below were derived from 79,743 subjects screened for participation in pharmaceutical clinical trials. The ECGs were measured and interpreted by US board-certified cardiologists using a high-resolution digital ECG viewing device.

Published Reference

Mason JW, Ramseth DJ, Chanter DO, Moon TE, Goodman DB, Mendzelevski B. Electrocardiographic reference ranges derived from 79,743 ambulatory subjects. J Electrocardiol 40:228–234, 2007.

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Normal Subject Subset

n = 46,129 — HR, PR, QRS, QRS Axis, QTcB, QTcF, QT by age & sex

Tables 2 & 3

Heart rate (beats/min)

Table 2

Group	2nd %ile	Median	98th %ile	N
All	48	68	98	46,129
Male	47	66	98	21,567
Female	49	68	98	24,562
0–9	60	84	120	963
10–19	49	70	101	1,345
M, 20–29	44	63	91	2,528
F, 20–29	49	69	96	2,469
30–69	48	68	97	33,685
70–99	46	65	93	5,139

Source: Mason JW et al. J Electrocardiol 40:228–234, 2007. Reference range subset (n = 46,129).

All 79,743 Subjects

Including normal and disease populations — HR, PR, QRS, QRS Axis, QT, QTcB, QTcF by age & sex

Tables 3–6

Heart rate (beats/min)

Table 3

Group	Mean	SD	Median	2nd %ile	98th %ile	1st %ile	99th %ile	N
All	68	12	67	47	97	45	102	79,487
Male	67	13	65	46	97	43	102	41,222
Female	69	12	68	49	97	47	103	38,265
0–9	85	15	84	60	120	58	129	990
10–19	71	13	70	48	100	46	105	1,477
20–29	67	12	66	46	95	43	98	6,086
30–39	69	12	68	48	95	46	100	9,569
40–49	69	12	68	48	96	46	101	15,392
50–59	68	12	67	48	97	46	102	18,578
60–69	67	12	65	46	96	44	102	16,585
70–79	65	12	64	45	95	43	101	8,432
80–89	65	12	64	46	95	44	101	2,259
90–99	70	15	66	45	125	43	146	119
M, 0–9	84	14	83	58	117	57	127	598
M, 10–19	70	13	69	47	99	45	106	847
M, 20–29	64	12	63	45	91	42	97	3,127
M, 30–39	67	12	66	46	95	44	99	4,605
M, 40–49	68	12	67	47	96	45	101	7,104
M, 50–59	68	12	66	47	97	45	102	9,936
M, 60–69	65	13	64	44	96	42	102	9,457
M, 70–79	64	13	62	44	96	42	102	4,509
M, 80–89	63	12	61	44	94	41	98	1,001
M, 90–99	64	11	62	43	95	43	95	38
F, 0–9	88	15	86	62	125	60	133	392
F, 10–19	73	12	71	53	101	50	105	630
F, 20–29	69	11	69	49	96	46	99	2,959
F, 30–39	70	11	69	50	96	48	100	4,964
F, 40–49	70	11	69	50	97	48	102	8,288
F, 50–59	69	11	68	49	96	47	102	8,642
F, 60–69	68	12	67	48	95	46	101	7,128
F, 70–79	67	12	66	46	95	44	101	3,923
F, 80–89	67	12	66	47	97	46	102	1,258
F, 90–99	72	16	69	46	144	44	147	81

Source: Mason JW et al. J Electrocardiol 40:228–234, 2007. All subjects (n = 79,487–79,743).