Proof-Load Tables — Metric Coarse
Proof loads for metric coarse-pitch bolts and screws, by property class. Proof load is the tension the part must hold without permanent stretch.
Proof load, kN (proof stress x stress area)
| Size | Stress area (mm²) | 4.6 | 8.8 | 10.9 | 12.9 |
|---|---|---|---|---|---|
| M5 x 0.8 | 14.2 | 3.2 | 8.2 | 11.8 | 13.8 |
| M6 x 1 | 20.1 | 4.5 | 11.7 | 16.7 | 19.5 |
| M8 x 1.25 | 36.6 | 8.2 | 21.2 | 30.4 | 35.5 |
| M10 x 1.5 | 58.0 | 13.0 | 33.6 | 48.1 | 56.2 |
| M12 x 1.75 | 84.3 | 19.0 | 48.9 | 69.9 | 81.7 |
| M14 x 2 | 115.4 | 26.0 | 67.0 | 95.8 | 112.0 |
| M16 x 2 | 156.7 | 35.3 | 90.9 | 130.0 | 152.0 |
| M20 x 2.5 | 244.8 | 55.1 | 146.9 | 203.2 | 237.5 |
| M24 x 3 | 352.5 | 79.3 | 211.5 | 292.6 | 341.9 |
| M30 x 3.5 | 560.6 | 126.1 | 336.4 | 465.3 | 543.8 |
| M36 x 4 | 816.7 | 183.8 | 490.0 | 677.9 | 792.2 |
Proof stress: 4.6 = 225 MPa; 8.8 = 580 MPa to M16, 600 MPa above; 10.9 = 830 MPa; 12.9 = 970 MPa. Calculated values; the ISO table rounds slightly differently.
These tables carry the same figures as the printed sheet below.
The printed sheet
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Text version of this sheet
ISO 898-1 proof loads · metric coarse pitch
What it is
FIELD IDENTIFICATION
Proof loads for metric coarse-pitch bolts and screws, by property class. Proof load is the tension the
part must hold without permanent stretch.
Proof load: the tension a bolt must hold
without permanent stretch
Proof load, kN (proof stress x stress area)
Size
Stress area (mm²)
4.6
8.8
10.9
12.9
M5 x 0.8
14.2
3.2
8.2
11.8
13.8
M6 x 1
20.1
4.5
11.7
16.7
19.5
M8 x 1.25
36.6
8.2
21.2
30.4
35.5
M10 x 1.5
58.0
13.0
33.6
48.1
56.2
M12 x 1.75
84.3
19.0
48.9
69.9
81.7
M14 x 2
115.4
26.0
67.0
95.8
112.0
M16 x 2
156.7
35.3
90.9
130.0
152.0
M20 x 2.5
244.8
55.1
146.9
203.2
237.5
M24 x 3
352.5
79.3
211.5
292.6
341.9
M30 x 3.5
560.6
126.1
336.4
465.3
543.8
M36 x 4
816.7
183.8
490.0
677.9
792.2
Proof stress: 4.6 = 225 MPa; 8.8 = 580 MPa to M16, 600 MPa above; 10.9 = 830 MPa; 12.9 = 970 MPa. Calculated values; the ISO table rounds slightly differently.
Key points
Fine pitch needs its own stress area and its own table.
Governing standards: ISO 898-1:2013; ISO 724 / ISO 898-1 stress area. Editions shown are the latest confirmed as of September 2026. The drawing and the governing standard
always take precedence over this sheet.
torquing any fastener. Verify the current governing standard, project documents, OEM requirements, size, thread, coating and lot certification. To the fullest extent permitted by law, The Fastener App disclaims liability
arising from reliance on this reference.
Fastener Guide reference FG-763133 · thefastenerapp.com/fastener-guide/technical-reference/proof-load-tables-metric-coarse · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.
