M10×0.75 Thread Dimensions and Tap Drill

M10×0.75 is an ISO metric fine-pitch thread: the 10 mm diameter with a 0.75 mm pitch (33.9 threads per inch) instead of the coarse 1.5 mm of M10×1.5. The thread is 0.41 mm shallower, so the tensile stress area rises from 58 to 67.9 mm² (17% more) and the lead angle falls from 3.03° to 1.44°.

Thread profile

major Ø10 mm10 threads = 7.5 mm
M10×0.75 drawn to scale: 31 threads in 22.9 mm of length.
60°Nut (internal thread)Bolt (external thread)P = 0.75 mmmajor Ø d10.000 mmpitch Ø d29.513 mmminor Ø D19.188 mm5H/8 = 0.406 mmthread axis
Basic profile with the M10×0.75 dimensions. The nut and bolt share the same pitch diameter.

M10×0.75 basic dimensions

Dimensionmmin
Major diameter d = D10.0000.3937
Pitch P0.7500.0295
Pitch diameter d2 = D29.5130.3745
Minor diameter, internal thread D19.1880.3617
Minor diameter, external thread d39.0800.3575
Height of fundamental triangle H0.6500.0256
Thread height, internal (5H/8)0.4060.0160
Thread height, external (17H/24)0.4600.0181
Crest flat of external thread (P/8)0.0940.0037
Crest flat of internal thread (P/4)0.1880.0074
PropertyValue
Threads per inch33.87
Flank angle60° (30° each side)
Lead angle at the pitch diameter1.44°
Tensile stress area As67.9 mm² (0.105 in²)

Basic (nominal) sizes per ISO 724, before tolerances. d3 is the root diameter of a bolt with the rounded root that ISO 898-1 uses for the stress area.

M10×0.75 tolerance limits (6g bolt, 6H nut)

6g and 6H are the general-purpose tolerance classes for commercial screws and nuts. The 6g screw has a fundamental deviation of 22 µm, so even at its largest it sits 0.022 mm below the basic size and leaves room for a thin plating.

External thread 6gMax (mm)Min (mm)Tolerance (mm)
Major diameter d9.9789.8380.140
Pitch diameter d29.4919.3910.100
Internal thread 6HMax (mm)Min (mm)Tolerance (mm)
Minor diameter D19.3789.1880.190
Pitch diameter D29.6459.5130.132

Computed from the ISO 965-1 deviations and tolerances for normal length of engagement; the results match the limits tabulated in ISO 965-2.

M10×0.75 tap drill size

Tap drill for M10×0.75: 9.2 mm

This leaves about 82% thread in the tapped hole.

The rule for metric tap drills is diameter minus pitch: 10 − 0.75 = 9.25 mm. Tap drill tables round this to 9.2 mm, a stocked drill size.

The 6H minor diameter of the finished nut thread must lie between 9.188 and 9.378 mm. The recommended drill falls inside that band.

Other drills that work for M10×0.75

A larger drill cuts less thread and taps more easily; a smaller one gives a fuller thread but loads the tap harder.

Drillmmin% threadWithin 6H limitsThread engagement
23/64" (0.3594 in)9.130.359489%no
9.2 mmrecommended9.200.362282%yes
9.25 mm9.250.364277%yes
9.3 mm9.300.366172%yes
9.4 mm9.400.370162%no
9.5 mm9.500.374051%no

% thread = (major diameter − drill diameter) ÷ (1.299 × pitch). See the tap drill chart for how to choose a percentage.

Clearance hole for M10

The clearance hole depends only on the 10 mm diameter, not on the pitch. The medium series, 11 mm, is the usual choice for general assembly.

SeriesHole Ø (mm)Hole Ø (in)Clearance on Ø (mm)
Fine (H12)10.50.41340.5
Medium (H13)110.43311
Coarse (H14)120.47242

Hole diameters from ISO 273.

M10×0.75 strength

ISO 898-1 tabulates fine-pitch loads only for a selected set of threads from M8×1 to M39×3, so it gives no proof or breaking loads for M10×0.75. For an estimate, multiply the tensile stress area of 67.9 mm² by the stress of the material: for example, 800 MPa gives 54.3 kN.

M10 pitches compared

All standard pitches on the M10 diameter. A finer pitch gives a shallower thread, a larger core and a smaller lead angle; a coarser pitch is faster to assemble and more tolerant of damage and plating.

M10×1.5depth 0.812 mmM10×1.25depth 0.677 mmM10×1depth 0.541 mmM10×0.75depth 0.406 mm
M10 pitches at the same scale with crests aligned; M10×0.75 is outlined.
ThreadPitch (mm)Pitch Ø (mm)Minor Ø D1 (mm)Stress area (mm²)Tap drill
M10×1.51.59.0268.376588.5 mm
M10×1.251.259.1888.64761.28.8 mm
M10×119.3508.91764.59 mm
M10×0.750.759.5139.18867.99.2 mm

When to choose a coarse or a fine thread

Closest inch thread

No inch thread is interchangeable with M10×0.75. The nearest is 3/8-32 UNEF, which is 0.48 mm smaller in diameter with a pitch of 0.794 mm against 0.750 mm. A nut may start on the wrong thread and then bind or strip, so identify by both diameter and pitch.

ThreadMajor Ø (mm)Pitch (mm)TPIØ difference (mm)
M10×0.75 (this thread)10.0000.75033.87—
3/8-32 UNEF9.5250.79432.00-0.475
3/8-24 UNF9.5251.05824.00-0.475
3/8-16 UNC9.5251.58716.00-0.475

Identify a thread from measurements

How the M10×0.75 dimensions are calculated

Every basic dimension follows from the major diameter and the pitch:

  • P = 0.75 mm
  • H = 0.866025 × P = 0.650 mm
  • d2 = d − 0.649519 × P = 10 − 0.487 = 9.513 mm
  • D1 = d − 1.082532 × P = 10 − 0.812 = 9.188 mm
  • d3 = d − 1.226869 × P = 10 − 0.920 = 9.080 mm (external root, 17H/24 deep)
  • As = π/4 × ((d2 + d3) ÷ 2)² = π/4 × 9.296² = 67.88 mm²
  • Lead angle = arctan(P ÷ (π × d2)) = 1.44°

Related sizes and tools

Sources: ISO 68-1 and ISO 724 (profile and basic dimensions), ISO 261 (diameter and pitch series), ISO 965-1 (tolerances), ISO 273 (clearance holes), ISO 898-1 (mechanical properties) and tap drill tables based on ISO 2306. How this site checks its data. Last reviewed 29 September 2026.