Dimensions mm · values as the standard states them Size P s m M2 0.4 4
≥ 1.2
M2.5 0.45 5
≥ 1.4
M3 0.5 5.5
≥ 1.6
M4 0.7 7
≥ 1.8
M5 0.8 8
≥ 2.3
M6 1 10
≥ 2.72
M8 1.25 13
≥ 3.52
M10 1.5 17
≥ 4.52
Ranges read min – max; ≤ / ≥ where the standard gives one limit, ≈ for approximate values. Sizes in (brackets) are non-preferred. Select a row for its size sheet.
Size sheet · DIN 562
M2
s width across flats 4
m nut height ≥ 1.2 Thread · ISO 261/262
Pitch P 0.4
d2 1.74
d3 1.509
Tap drill 1.6
Stress area As 2.07 mm² Size sheet · DIN 562
M2.5
s width across flats 5
m nut height ≥ 1.4 Thread · ISO 261/262
Pitch P 0.45
d2 2.208
d3 1.948
Tap drill 2.05
Stress area As 3.39 mm² Size sheet · DIN 562
M3
s width across flats 5.5
m nut height ≥ 1.6 Thread · ISO 261/262
Pitch P 0.5
d2 2.675
d3 2.387
Tap drill 2.5
Stress area As 5.03 mm² Size sheet · DIN 562
M4
s width across flats 7
m nut height ≥ 1.8 Thread · ISO 261/262
Pitch P 0.7
d2 3.545
d3 3.141
Tap drill 3.3
Stress area As 8.78 mm² Size sheet · DIN 562
M5
s width across flats 8
m nut height ≥ 2.3 Thread · ISO 261/262
Pitch P 0.8
d2 4.48
d3 4.019
Tap drill 4.2
Stress area As 14.18 mm² Size sheet · DIN 562
M6
s width across flats 10
m nut height ≥ 2.72 Thread · ISO 261/262
Pitch P 1
d2 5.35
d3 4.773
Tap drill 5
Stress area As 20.12 mm² Size sheet · DIN 562
M8
s width across flats 13
m nut height ≥ 3.52 Thread · ISO 261/262
Pitch P 1.25
d2 7.188
d3 6.466
Tap drill 6.75
Stress area As 36.61 mm² Size sheet · DIN 562
M10
s width across flats 17
m nut height ≥ 4.52 Thread · ISO 261/262
Pitch P 1.5
d2 9.026
d3 8.16
Tap drill 8.5
Stress area As 57.99 mm² Provenance
Draft — values taken from a single source and not yet cross-checked.
fasteners.eu dimensions, lengths, materials, property classes, current norm, equivalent norms Accessed 2026-09-23 · For design and safety-critical use, consult the current edition of the standard.