What is the difference between ISO 4014 and ISO 4017?

ISO 4014 covers hex head bolts with a partial thread (shank), while ISO 4017 covers hex head screws that are fully threaded. Both share the same head dimensions but differ in thread length.

How is bolt thread length calculated?

Per ISO 4014, thread length b = 2d + 6 for bolts ≤125mm, b = 2d + 12 for 125 200mm, where d is nominal diameter and L is bolt length.

How do you calculate bolt weight?

Bolt mass is estimated from the volume of the head (hexagonal prism) plus the shank (cylinder) multiplied by steel density (7850 kg/m³). The thread reduces the effective diameter slightly, so actual mass may be 2-5% less.

What is the head size for an M10 bolt?

Per ISO 4014/4017, an M10 hex bolt has a head width across flats (s) of 16 mm, width across corners of 18.48 mm, and head height (k) of 6.4 mm.

Are ISO 4014 dimensions the same as DIN 931?

ISO 4014 replaced DIN 931. The dimensions are very similar but not identical. ISO 4014 has slightly different tolerances on some sizes. For new designs, always use ISO 4014.

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Bolt Dimensions & Weight Lookup

Look up metric hex bolt dimensions and estimate mass per ISO 4014/4017. Select bolt size and length.

ISO 4014ISO 4017DIN 931/933

Results

Estimated Mass

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Head Width Across Flats (s)

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Head Height (k)

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Thread Length (b)

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Thread Pitch (P)

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Thread Length (ISO 4014)

Mass Estimation

Where ρ = 7850 kg/m³ for carbon steel. The head is approximated as a cylinder of diameter s.

Standard Dimensions

Size	s (mm)	k (mm)	P (mm)
M6	10	4.0	1.0
M8	13	5.3	1.25
M10	16	6.4	1.5
M12	18	7.5	1.75
M16	24	10.0	2.0
M20	30	12.5	2.5
M24	36	15.0	3.0
M30	46	18.7	3.5
M36	55	22.5	4.0

⚠️ Note: Mass is approximate. Actual mass depends on exact tolerances and plating. Use manufacturer data for precision ordering.

Bolt Dimensions & Weight Calculator | ISO 4014/4017 | Free Online Tool

Published by admin on February 15, 2026 February 15, 2026

Results

Thread Length (ISO 4014)

Mass Estimation

Standard Dimensions