BoltLabM10 Bolt Load Capacity
An M10 bolt's tensile load capacity depends on its thread pitch (coarse M10×1.5 or fine M10×1.25), its property class, and a safety factor you choose — there is no single "M10 capacity" figure that applies to every part sold as M10.
Use the Bolt Load Capacity Calculator to enter your own size, class, and safety factor; this page walks through how those inputs combine specifically for M10.
M10 thread geometry
M10 is offered in a coarse and a fine pitch, both supported by BoltLab's calculator:
| Designation | Nominal diameter | Pitch | Series |
|---|---|---|---|
| M10 × 1.5 | 10 mm | 1.5 mm | Coarse |
| M10 × 1.25 | 10 mm | 1.25 mm | Fine |
M10 × 1.5 is the coarse pitch most commonly stocked for general-purpose use; M10 × 1.25 fine-pitch fasteners are more often specified where a slightly larger stress area or finer adjustment is wanted, such as some automotive applications.
M10 tensile stress area
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Computed live using At = 0.7854 × (D − 0.938194 × P)². BoltLab's own sourcing work cross-checked the M10 × 1.5 result (57.99 mm²) directly against a quoted manufacturer table value of 58 mm² — see tensile stress area for the full derivation.
Property classes supported for M10
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All source-verified ISO metric classes in BoltLab's dataset cover the 10 mm diameter. See fastener property classes for sourcing and which classes are currently held back.
Example M10 capacity calculations
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Each row uses a safety factor of 4, shown for illustration only — substitute the factor appropriate to your application in the calculator. These numbers come from the same formula and data code the calculator itself runs, so this table and the tool can never disagree.
The role of safety factor for M10
The proof-based figure above is a ceiling before margin is applied, not a working limit on its own — dividing by an appropriate safety factor accounts for load uncertainty, manufacturing tolerance, and how serious a failure would be in your application. BoltLab does not suggest a default safety factor for M10 or any other size; see Bolt Load Capacity Basics for why no single value applies universally across applications and design codes.
Practical interpretation
M10 is one of the more frequently specified metric structural and automotive fastener sizes, often used where a step up in capacity from M8 is needed without moving to a substantially larger fastener. As with any size, the property class actually stamped on the bolt head — not the size alone — determines most of its real capacity: an M10 class 4.6 bolt and an M10 class 10.9 bolt share the same tensile stress area but differ in proof-based capacity by more than 3.5×. Always read the head marking (see Bolt Head Markings) rather than assuming a class from size or appearance.
Limitations
This page and the calculator behind it estimate fastener tensile capacity only — not shear, joint, thread-stripping, nut, connected-material, fatigue, or preload behavior. See the calculator's own limitations section for the complete list, and verify safety-critical work with a qualified engineer and the applicable design code.