Exact inch to millimeter reference

1-1/2 inches to mm: 38.1000 mm

Convert 1-1/2 inches to millimeters for CNC setup sheets, drawings, inspection notes, and supplier communication. The formula uses the exact international inch standard.

Answer first

1-1/2 inches =

38.1000 mm

2 decimals: 38.10
3 decimals: 38.100
4 decimals: 38.1000

Formula and precision policy

mm = inch × 25.4 → 1.5 × 25.4 = 38.1000 mm

The exact conversion uses 1 inch = 25.4 mm. This page displays 38.1000 mm by default. For CNC, inspection, RFQ, or supplier documents, keep the precision required by the drawing, tolerance block, process plan, or inspection equipment.

Equivalent forms

1-1/2 inches = 1.5 inch
1.5 inch × 25.4 = 38.1000 mm
38.10 mm rounded to 2 decimals; 38.100 mm rounded to 3 decimals

Nearby inch to mm values

Value	Decimal inch	Millimeters	Reference
1-1/4 inches	1.25	31.7500 mm	Open page
7/8 inch	0.875	22.2250 mm	Open page
3/4 inch	0.75	19.0500 mm	Open page
5/8 inch	0.625	15.8750 mm	Open page
1/2 inch	0.5	12.7000 mm	Open page
7/16 inch	0.4375	11.1125 mm	Open page

Manufacturing context and caveat

A 1-1/2 inch dimension is common in layout and material contexts. The result is a nominal conversion before process-specific allowance.

Reference-only caveat: this conversion does not certify tolerance, fit, pressure, load, code compliance, material equivalence, or interchangeability. Confirm the controlling drawing, standard, supplier data, and engineering approval before manufacturing.

FAQs

How many millimeters is 1-1/2 inches?

1-1/2 inches equals 38.1000 mm using the exact conversion factor 1 inch = 25.4 mm.

What formula converts 1-1/2 inches to mm?

Use mm = inch × 25.4. For this page, 1.5 × 25.4 = 38.1000 mm.

Should I round 38.1000 mm for CNC or inspection work?

Use the precision required by the drawing, process plan, or inspection method. This page shows 38.10 mm, 38.100 mm, and 38.1000 mm so you can choose the appropriate display precision.

Is 1-1/2 inches the same as 1.5 inch?

Yes. 1-1/2 inches is represented here as 1.5 inch before multiplying by 25.4 to get millimeters.

Can this conversion decide fit, tolerance, or replacement parts?

No. This is a reference unit conversion only. Confirm drawing tolerances, standards, material specifications, supplier certificates, and engineering approval before manufacturing or substituting parts.