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Metric Bolt Torque Chart

Bolts

Metric bolts have their own standards and while similar to like-sized bolts in SAE (U.S.) patterns, their grading and torque specifications are different.

The amount of torque safely allowed on a bolt will depend on its diameter, the grade of the metal it's made from, and the application at hand. The following are bolt torques for common sizes and standard grades:

Metric Bolts
Maximum Torque in ft lbs for clean, dry threads
Bolt Size Low Grade Grade 8.8 Grade 10.9 Grade 12.9
6mm 3-5lb 7lb 10lb 12lb
8mm 8-12lb 17lb 24lb 29lb
10mm 15-22lb 33lb 47lb 57lb
12mm 39lb 59lb 83lb 100lb
14mm 60lb 101lb 131lb 158lb
16mm 60-94lb 146lb 202lb 247lb
18mm 60-130lb 201lb 283lb 340lb
20mm 166-188lb 285 lb 401lb 482lb

The above chart is not definitive, of course. Shop manuals, manufacturer's specifics, and other values for the specific application or hardware being used will determine actual values.

To determine the grade of the bolt being used, on metrics it is usually indicated on the hex head by a number corresponding to the grade (i.e. "8.8" is 8.8 grade). Bolts with different heads, such as torques or female hex patterns, will have the grade stamped underneath the head or at the bolt's heel.

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