Proof-Load Tables - Metric Fine
Proof loads for metric fine-pitch bolts and screws. Fine pitch has a larger stress area than coarse at the same diameter, so proof loads are higher.
Proof load, kN (proof stress x stress area)
| Size | Stress area (mm²) | 8.8 | 10.9 | 12.9 |
|---|---|---|---|---|
| M8 x 1 | 39.2 | 22.7 | 32.5 | 38.0 |
| M10 x 1.25 | 61.2 | 35.5 | 50.8 | 59.4 |
| M10 x 1 | 64.5 | 37.4 | 53.5 | 62.6 |
| M12 x 1.25 | 92.1 | 53.4 | 76.4 | 89.3 |
| M12 x 1.5 | 88.1 | 51.1 | 73.1 | 85.5 |
| M14 x 1.5 | 124.5 | 72.2 | 103.4 | 120.8 |
| M16 x 1.5 | 167.2 | 97.0 | 138.8 | 162.2 |
| M18 x 1.5 | 216.2 | 129.7 | 179.5 | 209.7 |
| M20 x 1.5 | 271.5 | 162.9 | 225.3 | 263.4 |
| M22 x 1.5 | 333.1 | 199.8 | 276.4 | 323.1 |
| M24 x 2 | 384.4 | 230.6 | 319.1 | 372.9 |
| M30 x 2 | 621.2 | 372.7 | 515.6 | 602.6 |
Proof stress: 8.8 = 580 MPa to M16, 600 MPa above; 10.9 = 830 MPa; 12.9 = 970 MPa. Stress area = pi/4 x (d - 0.9382 P) squared. Calculated values.
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 fine pitch
What it is
FIELD IDENTIFICATION
Proof loads for metric fine-pitch bolts and screws. Fine pitch has a larger stress area than coarse at
the same diameter, so proof loads are higher.
Proof load: the tension a bolt must hold
without permanent stretch
Proof load, kN (proof stress x stress area)
Size
Stress area (mm²)
8.8
10.9
12.9
M8 x 1
39.2
22.7
32.5
38.0
M10 x 1.25
61.2
35.5
50.8
59.4
M10 x 1
64.5
37.4
53.5
62.6
M12 x 1.25
92.1
53.4
76.4
89.3
M12 x 1.5
88.1
51.1
73.1
85.5
M14 x 1.5
124.5
72.2
103.4
120.8
M16 x 1.5
167.2
97.0
138.8
162.2
M18 x 1.5
216.2
129.7
179.5
209.7
M20 x 1.5
271.5
162.9
225.3
263.4
M22 x 1.5
333.1
199.8
276.4
323.1
M24 x 2
384.4
230.6
319.1
372.9
M30 x 2
621.2
372.7
515.6
602.6
Proof stress: 8.8 = 580 MPa to M16, 600 MPa above; 10.9 = 830 MPa; 12.9 = 970 MPa. Stress area = pi/4 x (d - 0.9382 P) squared. Calculated values.
Key points
Always confirm the pitch with a gauge: M12 x 1.25 and M12 x 1.5 both exist.
Governing standards: ISO 898-1:2013; ISO 261. 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-303CE7 · thefastenerapp.com/fastener-guide/technical-reference/proof-load-tables-metric-fine · © The Fastener App. Reference only — verify the current governing standard, drawing and manufacturer data before specifying or installing.
