508 millimeters equals approximately 20.0 inches.
The conversion from millimeters to inches involves dividing the millimeter value by 25.4, since one inch equals exactly 25.4 millimeters. So, 508 mm divided by 25.4 gives the result in inches.
Conversion Tool
Result in inches:
Conversion Formula
To convert millimeters (mm) to inches (in), divide the millimeter measurement by 25.4. This works because one inch is standardized as exactly 25.4 millimeters. So, the formula is:
inches = millimeters ÷ 25.4
This formula works because millimeter and inch are both units of length, but from different measurement systems, metric and imperial respectively. By dividing by 25.4, you find how many inches fit inside the given millimeters.
Example: Convert 508 mm to inches step-by-step:
- Start with 508 mm.
- Divide 508 by 25.4: 508 ÷ 25.4 = 20.
- So, 508 mm equals 20 inches.
Conversion Example
- Convert 254 mm to inches:
- Divide 254 by 25.4 → 254 ÷ 25.4 = 10.
- Therefore, 254 mm equals 10 inches.
- Convert 762 mm to inches:
- 762 ÷ 25.4 = 30.
- So, 762 mm equals 30 inches.
- Convert 100 mm to inches:
- 100 ÷ 25.4 ≈ 3.937.
- Thus, 100 mm is about 3.937 inches.
- Convert 127 mm to inches:
- 127 ÷ 25.4 = 5.
- So, 127 millimeters equals 5 inches.
Conversion Chart
The table below shows millimeter values from 483.0 to 533.0 and their inch equivalents. Use the chart to quickly find how many inches correspond to a millimeter measurement within this range without calculation.
| Millimeters (mm) | Inches (in) |
|---|---|
| 483.0 | 19.0157 |
| 488.0 | 19.2126 |
| 493.0 | 19.4094 |
| 498.0 | 19.6063 |
| 503.0 | 19.8031 |
| 508.0 | 20.0000 |
| 513.0 | 20.1969 |
| 518.0 | 20.3937 |
| 523.0 | 20.5906 |
| 528.0 | 20.7874 |
| 533.0 | 20.9843 |
Related Conversion Questions
- How many inches are in 508 millimeters exactly?
- Is 508 mm more or less than 20 inches?
- What is 508 mm converted to inches with decimals?
- Can I convert 508 mm to inches without a calculator?
- Why does 508 millimeters equal 20 inches?
- How precise is the conversion of 508 mm to inches?
- What inches measurement corresponds closest to 508 mm?
Conversion Definitions
Millimeter (mm): A millimeter is a unit of length in the metric system, equal to one thousandth of a meter. It is used to measure small distances or thicknesses and is commonly applied in engineering, manufacturing, and daily measurements where precision is required.
Inch (in): An inch is a unit of length in the imperial system, defined as exactly 25.4 millimeters. It is used mostly in the United States and some other countries for measuring length, width, and height in everyday objects, construction, and various industries.
Conversion FAQs
Why is one inch equal to 25.4 millimeters?
The inch was officially defined as exactly 25.4 millimeters in 1959 during an international agreement among countries using the imperial and metric systems. This fixed value helps standardize measurements and avoid confusion when converting between the two units.
Can I convert millimeters to inches by multiplying instead of dividing?
No, you cannot multiply to convert millimeters to inches. Because one inch contains 25.4 millimeters, to find how many inches fit in a certain number of millimeters, you must divide the millimeters by 25.4. Multiplying would give an incorrect, larger value.
What’s the best way to round inches after conversion?
It depends on the needed precision. For rough estimates, rounding to the nearest whole inch works. For engineering or detailed work, rounding to two or four decimal places provides better accuracy. The conversion tool above shows results to four decimals by default.
Are there tools other than manual calculation for mm to inches?
Yes, many online converters, smartphone apps, and calculator functions exists for instant conversion. The tool in the Conversion Tool section uses JavaScript to provide immediate results as you enter values, making conversions quick and easy without manual math.
Does the conversion factor 25.4 ever change?
No, the conversion factor of 25.4 millimeters per inch is fixed by international agreement. It’s a precise value used worldwide in science, engineering, and commerce to keep units consistent and conversions accurate.
Last Updated : 29 June, 2025
I’ve put so much effort writing this blog post to provide value to you. It’ll be very helpful for me, if you consider sharing it on social media or with your friends/family. SHARING IS ♥️
Sandeep Bhandari holds a Bachelor of Engineering in Computers from Thapar University (2006). He has 20 years of experience in the technology field. He has a keen interest in various technical fields, including database systems, computer networks, and programming. You can read more about him on his bio page.