You are buying a 55-inch TV and need to know if it fits a 120 cm cabinet, or you are given a pipe as 3/4" and need its diameter in millimeters to order the part. The tape shows fractions and your head wants decimals.
How to use Inches to cm step by step
1. Choose the direction
"Inches → cm" for plans, screens or pipes, or "cm → inches" for the reverse.
2. Type the measurement
It accepts decimals (3.5), fractions (3 1/2, 5/8) and feet with inches (5'7").
3. Copy the value you need
You get cm, mm, decimal inches, a 1/16 fraction and feet-inches; copy each with one click.
The Step Count: Traditional Friction vs. KorexTools
Turning an inch fraction into centimeters by hand
- Convert the fraction to a decimal (3 1/2 = 3.5).
- Multiply by 2.54.
- Round to the precision you need.
- Repeat if you are given feet and inches.
With KorexTools Inches to Centimeters
- Type the measurement as it appears on the tape.
- Read cm and mm.
- Copy the value you need.
Inches to centimeters when the measurement comes in tape-measure fractions
An inch is exactly 2.54 cm (25.4 mm), but you rarely get clean decimals: a tape measure reads 3 1/2, 5/8 or 11 3/16. Converting those fractions by hand is where errors creep into carpentry, plumbing, clothing and plans.
For TVs and monitors the figure is the diagonal: a 55-inch TV is 139.7 cm across the diagonal, not the width. And for height, 5'7" is 67 inches, or 170.18 cm. The converter understands all three formats and also returns the nearest 1/16-inch fraction so you can go back to the tape.
What each measurement returns
- •Exact centimeters and millimeters using 25.4 mm per inch.
- •Decimal inches and the nearest 1/16-inch fraction.
- •Feet and inches (5'7") for heights and construction measures.
- •A table of 25 common sizes, from 1/8" to 65", for a quick look.
Common equivalents
| Inches | Centimeters | Typical use |
|---|---|---|
| 1" | 2.54 cm | Reference |
| 3 1/2" | 8.89 cm | Screws, profiles |
| 55" | 139.7 cm | TV diagonal |
| 5'7" | 170.18 cm | Height |
Common Mistakes and How to Avoid Them
- ⚠️Reading 3 1/2 as 3.12 instead of 3.5.
- ⚠️Mixing up inches (") and feet (') when transcribing a measurement.
Frequently Asked Questions
How many centimeters is 55 inches?
139.7 cm. Multiply by 2.54. On a TV, that figure is the screen diagonal.
How do I type a fraction like 3 1/2?
With a space between the whole and the fraction (3 1/2) or a hyphen (3-1/2). 5/8 alone or the decimal 3.5 also work.
How do I convert 5'7" to centimeters?
5 feet is 60 inches and 7 more makes 67; times 2.54 is 170.18 cm. Type it as is (5'7") and the converter does the maths.
Why is the fraction approximate?
The fraction is rounded to 1/16 inch, the usual precision of a tape measure. Centimeters and millimeters are exact.
What I would do if I were in your shoes
«If a measurement goes to a part that will be cut or bought, convert both ways: inches to cm and back to the fraction. If you do not recover what was on the tape, something failed.» — DataKorex Engineering Team