20mm to Inches
Convert 20 millimeters to inches — instant, accurate, and easy
The Answer
Quick Answer: How Many Inches is 20mm?
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20mm equals 0.7874 inches (approximately 0.787402 inches, rounded to six decimal places). When converting 20mm to inches, 20 millimeters converts to 0.7874″ in decimal or 25/32″ in fractional form. 20mm is 0.95mm larger than 3/4″ (19.05mm).
The conversion of 20 mm to inches uses an exact conversion factor, because one inch equals exactly 25.4 millimeters by international standard. The four-decimal result is rounded, so it is approximate. Therefore, 20 divided by 25.4 gives approximately 0.7874 inches.
What is 20mm in Inches?
20mm in inches is 0.7874 inches. When you convert 20 millimeters, you get 0.787402 inches in decimal form. In fractional form (nearest 1/64″), 20mm equals approximately 25/32 of an inch.
Six-Decimal Value
20 mm in inches is approximately 0.787402 (rounded to six decimal places). For most practical purposes, 0.7874″ (4 decimal places) is more than accurate enough for measurements in construction, hardware, jewelry, and everyday use.
How to Convert 20mm to Inches
Converting 20mm to inches is simple. Use this formula:
Applying this to 20 mm:
Step-by-Step Guide
- Take the millimeter value: 20 mm
- Divide by 25.4: 20 ÷ 25.4
- Get the decimal inches: 0.7874″
- Convert to fraction (optional): ≈ 25/32″
20 mm Compared With 3/4 and 13/16 Inch
20 mm is approximately 0.7874 inches. The nearest 1/16-inch mark is 13/16 inch, which is 20.6375 mm: 0.6375 mm above 20 mm.
A 3/4-inch measurement is 19.05 mm, which is 0.95 mm smaller than 20 mm.
Pipe sizes are nominal: a DN20 steel pipe (NPS 3/4) has an outside diameter of about 26.7 mm, not 20 mm. Check the actual outside diameter before buying fittings.
20mm to Inches Conversion Chart
| Unit | Value |
|---|---|
| Millimeters | 20 mm |
| Inches (decimal) | 0.7874″ |
| Inches (fraction) | 25/32″ |
| Centimeters | 2.00 cm |
| Feet | 0.0656 ft |
| Meters | 0.0200 m |
Values Near 20mm
| MM | Decimal Inches | Fractional |
|---|---|---|
| 17 mm | 0.6693″ | 43/64″ |
| 18 mm | 0.7087″ | 45/64″ |
| 19 mm | 0.7480″ | 3/4″ |
| 20 mm | 0.7874″ | 25/32″ |
| 21 mm | 0.8268″ | 53/64″ |
| 22 mm | 0.8661″ | 55/64″ |
| 23 mm | 0.9055″ | 29/32″ |
20 mm in Other Units
Millimeters convert cleanly into every other length unit. Here is 20 mm expressed seven different ways — useful when a drawing, spec sheet or supplier quotes a unit other than inches.
| Unit | 20 mm equals |
|---|---|
| Centimeters (cm) | 2 cm |
| Meters (m) | 0.02 m |
| Inches (in) | 0.7874 in |
| Feet (ft) | 0.0656 ft |
| Yards (yd) | 0.02187 yd |
| Thousandths of an inch (mil) | 787.4 mil |
| Typographic points (1/72 in) | 56.69 pt |
How Accurate Is Each Fraction of 20 mm?
20 mm equals 0.7874″ (rounded to four decimal places). Any fraction is a further rounding of the full-precision value, so each one carries a small error. This table shows the closest fraction at each common denominator and how far it actually sits from 20 mm.
| Rounded to | Fraction | Decimal | Fraction vs. original |
|---|---|---|---|
| Nearest 1/2″ | 1″ | 1.0000″ | +5.400 mm (above original) |
| Nearest 1/4″ | 3/4″ | 0.7500″ | −0.950 mm (below original) |
| Nearest 1/8″ | 3/4″ | 0.7500″ | −0.950 mm (below original) |
| Nearest 1/16″ | 13/16″ | 0.8125″ | +0.638 mm (above original) |
| Nearest 1/32″ | 25/32″ | 0.7813″ | −0.156 mm (below original) |
| Nearest 1/64″ | 25/32″ | 0.7813″ | −0.156 mm (below original) |
For woodworking, DIY and general workshop use, 25/32″ is the practical choice — it lands within 0.4 mm of 20 mm. For machining, toolmaking or CAD, use the decimal value 0.7874″ rather than any fraction.
Frequently Asked Questions: 20mm to Inches
How many inches is 20mm?
20mm equals 0.7874 inches, or approximately 25/32″ in fractional form.
What is 20mm in inches in fraction form?
20mm in fraction form is 25/32″ (rounded to nearest 1/64″).
How do I convert 20mm to inches?
Divide 20 by 25.4 to get inches. 20 ÷ 25.4 = 0.7874 inches.
How does 20 mm compare with 3/4″?
20mm is 0.95mm larger than 3/4″ (19.05mm)
How thick/wide is 20mm?
20mm is 0.7874″ or 2.00 centimeters. 20mm is close to 0.79 inches. Common for pipe diameters, larger cables, and standard tool sizes.
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Digital calipers typically display readings to 0.01 mm resolution, enough to check 20 mm (≈ 0.7874″). See current options:
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