Metric fine

M10 × 1.0

Tap drill 9 mm for a M10 × 1.0 thread - major Ø 10 mm, pitch 1 mm (≈25.4 TPI (converted)).

Tap drill
9 mm
9 mm · ≈77% thread

Profile

Thread form & key diameters

Major Ø 10 mmP 1 mm60°Minor Ø 8.773 mm · Pitch Ø 9.351 mmM10 × 1.025.4 TPI · 60° form

Dimensions

Dimensions, drill sizes and wrench sizes for M10 × 1.0.
DesignationM10 × 1.0
Major (outside) diameter10 mm · 0.3937"
Pitch1 mm · ≈25.4 TPI (converted)
Pitch diameter9.351 mm · 0.3681"
Minor diameter (external)8.773 mm · 0.3454"
Minor diameter (internal)8.918 mm · 0.3511"
Recommended tap drill9 mm · ≈77% thread
Clearance holeClose 10.5 · Normal 11 · Loose 12 mm
Hex head (across flats)16 mm
Socket key (across flats)8 mm

Wrench sizes follow ISO 4014 / ISO 4017. Older DIN 931 / DIN 933 bolts differ at several sizes (M10 = 17, M12 = 19, M14 = 22, M22 = 32) - check the bolt before choosing a spanner.

ISO 273 clearance holes (fine / medium / coarse).

M10 × 1.0 in numbers

M10 × 1.0 is 10 mm across the crests with a 1 mm pitch, which is 25.4 threads per inch. The basic pitch diameter is 9.351 mm and the bolt's minor diameter 8.773 mm, so the thread is 0.614 mm deep on the bolt. Its tensile stress area is 64.5 mm², 11% more than the coarser M10 × 1.5 at the same diameter. The nearest inch size, 3/8-16 UNC, is 0.47 mm smaller across the crests and its pitch is 0.588 mm coarser, so the two do not interchange.

Tap drill by thread percentage

Hole = D − % × 0.0129904 × P, with D = 10 mm and P = 1 mm. A smaller hole leaves more thread; the recommended 9 mm drill above gives about 77%.

Tap-drill hole diameters for M10 × 1.0 at several thread percentages.
ThreadHole (mm)Hole (in)
60%9.220.3630
65%9.160.3605
70%9.090.3579
75%9.030.3553

Tightening torque estimate

Target preload is 75% of proof load; torque is estimated from T = K · F · d.

Proof-load preload and estimated tightening torque for M10 × 1.0 by fastener grade or property class.
Grade / classStress areaPreloadTorque
Class 8.864.5 mm²28.05 kN56.1 N·m
Class 10.964.5 mm²40.15 kN80.3 N·m
Class 12.964.5 mm²46.92 kN93.8 N·m

Strengths are ISO 898-1:2013 Table 3 for d ≤ 16 mm. Class 8.8 is size-banded - 580 MPa proof at or below 16 mm, 600 MPa above - while 10.9 and 12.9 hold one value across the range.

These figures assume a nut factor of K = 0.20 (dry / as-received steel). K captures thread and head friction and can swing torque by 30% or more - a lubricated joint needs noticeably less. Change the lubrication assumption in the bolt-torque calculator.

Put M10 × 1.0 on a job sheet

The bolt schedule collects the fasteners for one job onto a single sheet - tap drill, wrench size, grade and tightening torque on every line, taken straight from pages like this one. Free schedules hold 3 lines and are saved in this browser only.

Open bolt schedule

What tap drill do I need for M10 × 1.0?

For a M10 × 1.0 thread, drill the hole with a 9 mm tap drill (9 mm - the standard D − P rule) before tapping. That produces roughly 77% thread engagement, the usual target for a strong, tappable hole. The mating bolt has a major diameter of 10 mm and a pitch of 1 mm (≈25.4 TPI (converted)).

To pass a M10 × 1.0 bolt through a part rather than thread it, use a clearance hole: Close 10.5 · Normal 11 · Loose 12 mm.

All values come from the standard thread formulas (ISO 68-1 / ASME B1.1) and published standard tables. See the full reference.

Frequently asked questions

What drill size do I need to tap a M10 × 1.0 thread?

Drill 9 mm before tapping M10 × 1.0. That leaves roughly 77% thread engagement, the usual target for a strong hole that still taps cleanly.

Is M10 × 1.0 a coarse or fine thread?

M10 × 1.0 is a metric fine thread. Its 1 mm pitch is tighter than the standard coarse pitch for M10, which suits thin walls, fine adjustment and vibration-sensitive joints.

What size clearance hole does a M10 × 1.0 bolt need?

Drill 10.5 mm for a close fit, 11 mm for a normal fit or 12 mm for a loose fit (ISO 273). A clearance hole lets the M10 × 1.0 bolt pass through the part instead of threading into it.

How much torque should I use on a M10 × 1.0 bolt?

Estimated tightening torque for M10 × 1.0 runs from 56.1 N·m (Class 8.8) to 93.8 N·m (Class 12.9), targeting 75% of proof load with a dry nut factor of K = 0.20. Lubricated threads need noticeably less torque.

Same diameter

Other M10 threads

Closest inch sizes

Inch equivalents for M10 × 1.0

Nearest standard Unified sizes by major diameter. These are substitutes by size only - the thread forms are not interchangeable, so never run one into the other.

Nearby sizes

More metric fine threads