REFERENCE TABLE #95 · CONSTRUCTION · FASTENERS
The right torque is what turns a bolt into a clamp. At the lookup default — a 1/2-inch SAE Grade 5 bolt — the dry-thread spec is 75 ft-lb (101.7 N·m). Use the full tables below for SAE Grades 2, 5, and 8 and metric Classes 8.8 and 10.9, or look up your exact fastener. All values are for dry, unlubricated threads: verify against the fastener manufacturer’s spec before torquing.
Pick a diameter and a grade or class. SAE grades pair only with inch sizes and metric classes only with metric sizes — mixing them is reported as an error, not guessed. The result converts ft-lb to newton-metres at 1 ft-lb = 1.35582 N·m.
Values are widely published consensus figures for dry, unlubricated, plain-finish threads at standard coarse pitch. Plated, oiled, or anti-seize-coated threads need lower torque for the same clamping force — typically 20–30% less — so always verify against the fastener manufacturer’s specification for your exact bolt, finish, and joint. Print this page for the shop wall with the print button above.
| Diameter | Grade 2 | Grade 5 | Grade 8 |
|---|---|---|---|
| 1/4" | 6 | 8 | 12 |
| 5/16" | 11 | 17 | 25 |
| 3/8" | 20 | 31 | 44 |
| 7/16" | 32 | 49 | 70 |
| 1/2" | 49 | 75 | 105 |
| 9/16" | 70 | 110 | 155 |
| 5/8" | 100 | 150 | 210 |
| 3/4" | 175 | 265 | 375 |
| 7/8" | 290 | 430 | 605 |
| 1" | 430 | 645 | 910 |
| Diameter | Class 8.8 | Class 10.9 |
|---|---|---|
| M6 | 7 | 10 |
| M8 | 17 | 25 |
| M10 | 34 | 49 |
| M12 | 59 | 85 |
| M14 | 94 | 135 |
| M16 | 145 | 208 |
| M18 | 202 | 290 |
| M20 | 286 | 410 |
| M22 | 387 | 553 |
| M24 | 493 | 705 |
Setup: 1/2-inch SAE Grade 5, dry thread.
Line 1 — find the row. The 1/2-inch row of the SAE table reads 49 / 75 / 105 ft-lb for Grades 2 / 5 / 8.
Line 2 — pick the grade. Grade 5 gives 75 ft-lb — the lookup default.
Line 3 — convert to newton-metres. 75 × 1.35582 = 101.7 N·m.
Line 4 — the sanity check. The same size in Grade 8 takes 105 ft-lb and in Grade 2 only 49 — so if your bolt head shows no grade marks (Grade 2) or six radial lines (Grade 8), the 75 ft-lb figure is wrong for your bolt. Read the head before you torque.
SAE Grade 2 bolts usually carry no markings. Grade 5 carries three radial lines, Grade 8 six radial lines. Metric Class 8.8 and 10.9 are stamped with those numbers on the head. If the head is unmarked and the application is metric, assume the lower class until you can verify — over-torquing a soft bolt stretches it permanently, and a stretched bolt never clamps properly again.
| Output | Formula | What it means |
|---|---|---|
| Dry torque (ft-lb) | table lookup by size + grade | 75 ft-lb at the default — the wrench setting for a dry 1/2" Grade 5 bolt. |
| Torque (N·m) | ft-lb × 1.35582 | 101.7 N·m — the same spec for a metric torque wrench. |
| Grade step | Grade 8 ÷ Grade 5, same size | 105 ÷ 75 = 1.40 — Grade 8 takes 40% more torque than Grade 5. |
| Size step | next size up, same grade | 3/4" Grade 5 at 265 ft-lb is 3.5× the 1/2" value — torque grows fast with diameter. |
These are widely published consensus values for dry, plain-finish, coarse-thread bolts; published tables disagree by a few percent from source to source, and fine threads, prevailing-torque nuts, washers, and joint stiffness all shift the correct value. Lubrication is the biggest variable: an oiled thread can reach the same clamp load at 20–30% less torque, so applying a dry spec to a lubricated bolt risks stripping or snapping it. Always verify against the fastener manufacturer’s specification for safety-critical joints (wheels, brakes, steering, structural steel). This chart is general reference information, not engineering advice for a specific joint.
Bright Side Kit. "Bolt Torque Chart: SAE & Metric Tightening Specs 2026." https://brightoolbox.com/bolt-torque-chart/ Accessed October 24, 2026.Data sources75 ft-lb dry, or 101.7 N·m. That is the consensus dry-thread value. If the threads are oiled or the bolt is plated, check the manufacturer’s lubricated spec — it will be lower, and using 75 ft-lb on a lubricated bolt can over-stretch it.
Strength — and therefore torque. Grade 8 bolts are heat-treated alloy steel, roughly 40% stronger than Grade 5 at the same size: a 1/2-inch Grade 8 takes 105 ft-lb versus 75 for Grade 5. Grade 8 is marked with six radial lines on the head; Grade 5 with three.
Dry, unlubricated threads. Lubrication dramatically lowers friction, so the same clamp load is reached at 20–30% less torque. Never apply a dry spec to an oiled, greased, or anti-seize-coated fastener without checking the lubricated table.
Multiply by 1.35582. So 75 ft-lb is 101.7 N·m, and 100 ft-lb is 135.6 N·m. The lookup on this page does the conversion for every size and grade automatically.
Because the manual is specific and this chart is generic. A manufacturer’s spec accounts for the exact bolt, finish, lubrication, washer, and joint in that application — and it always wins over a generic table. Use this chart when no manual spec exists, and the manual when it does.
It stretches permanently and clamps worse, not better. Past its yield point a bolt loses clamping force, and further tightening can snap it or strip the threads. An over-torqued bolt that feels tight can be weaker than a correctly torqued one — which is why a torque wrench beats an impact gun for final tightening.
They are strength classes stamped on the bolt head. Class 10.9 is stronger than 8.8: an M12 in 10.9 takes 85 ft-lb versus 59 for 8.8. The numbers encode tensile and yield strength, and like SAE grades, the higher class always takes more torque at the same size.
Only as a rough guide. Fine threads have slightly different torque values than the coarse-thread values tabulated here, usually a few percent lower for the same size and grade. For fine-thread or specialty fasteners, use the manufacturer’s table for that thread pitch.