Equivalent Standards

b - length of the thread (at least)
l - length of bolt
d - the nominal diameter of the thread
k - head height
dk - head diameter
m - groove width
a - length undercut
x - thread run
r - Head radius

DIN 7985 Dimensions for Pan Head Screws with Philip Drive

d	p	a	b	da	dk		k			r	rf	v	x	Cross Recess	Type H			Type Z
			+2,0												m	penetration depth		m	penetration depth
		max.	p	max	nominal = max.	min	nominal	max.	min.	min.	approx.	approx.	max.	No.	approx.	min	max.	approx.	min	max.
M1.6	0.35	0.7	15	2.1	3.2	2.9	1.3	1.42	1.18	0.1	3	0.8	0.9	0	1.8	0.72	1.02	1.8	0.92	1.17
M2	0.4	0.8	16	2.6	4	3.7	1.6	1.72	1.48	0.1	4	1.1	1	1	2.5	1.1	1.4	2.4	1.1	1.35
M2.5	0.45	0.9	18	3.1	5	4.7	2	2.12	1.88	0.1	5	1.3	1.1	1	2.7	1.3	1.6	2.6	1.27	1.52
M3	0.5	1	19	3.6	6	5.7	2.4	2.52	2.28	0.1	6	1.6	1.25	1	3.1	1.7	2	3	1.68	1.93
M3.5	0.6	1.2	20	4.1	7	6.64	2.7	2.82	2.58	0.2	7	1.9	1.5	2	4.2	1.74	2.24	4	1.65	2.11
M4	0.7	1.4	22	4.7	8	7.64	3.1	3.25	2.95	0.2	8	2	1.75	2	4.6	2.04	2.54	4.3	1.9	2.36
M5	0.8	1.6	25	5.7	10	9.64	3.8	3.95	3.65	0.2	10	2.5	2	2	5.3	2.77	3.27	5	2.64	3.1
M6	1	2	28	6.8	12	11.57	4.6	4.75	4.45	0.25	12	3	2.5	3	6.8	3.03	3.53	6.7	3.02	3.48
M8	1.25	2.5	34	9.2	16	15.57	6	6.15	5.85	0.4	16	3.7	3.2	4	9	4.18	4.68	8.8	4.06	4.52
M10	1.5	3	40	11.2	20	19.48	7.5	7.68	7.32	0.4	20	4.8	3.8	4	10.2	5.38	5.88	9.9	5.23	5.69