CodeKitHubWhat Is This Tool?
The inch is an imperial/US customary length unit, defined since 1959 as exactly 25.4 millimeters — that is, 1 inch = 2.54 cm. The centimeter is one hundredth of a meter, the base length unit of the metric system used by most of the world.
The inch survives internationally in one place above all: screen diagonals. Phone, tablet, laptop, monitor and TV sizes are quoted in inches everywhere, even in fully metric countries — which is why questions like "6.1 inches in cm" are searched millions of times a month.
Why Use It?
- Bidirectional and instant: type in either field and the other converts as you type — no button to press.
- Exact by definition: the conversion uses 1 inch = 2.54 cm, the official value, not an approximation.
- Screen-size chart included: 5.1" to 65" diagonals converted to centimeters, with the typical device for each size.
- Handles decimals: 6.1, 10.9, 15.6 — the sizes real devices actually come in.
- Free, private, works on your phone: everything runs in your browser, nothing is uploaded.
How to Use
- Type a value in the inches field to see it in centimeters — or type in the centimeters field to see inches.
- Use decimals freely: 6.1 inches, 12.9 inches, 34.5 cm all work.
- For screen sizes, check the chart below the converter — common phone, tablet, laptop, monitor and TV diagonals are pre-converted.
- For small everyday lengths, use the 1–12 inch table.
Example
Input
6.1 inches (a common phone screen diagonal)Output
15.49 cm6.1 × 2.54 = 15.494, rounded to 15.49 cm. Remember a screen diagonal measures corner to corner, not width or height.
Common screen sizes in inches and centimeters
| Inches | Centimeters | Typical device |
|---|---|---|
| 5.1" | 12.95 cm | Compact phone |
| 5.5" | 13.97 cm | Small phone |
| 6.1" | 15.49 cm | Standard phone |
| 6.7" | 17.02 cm | Large phone |
| 7.9" | 20.07 cm | Small tablet |
| 10.1" | 25.65 cm | Tablet |
| 10.9" | 27.69 cm | Tablet |
| 12.9" | 32.77 cm | Large tablet |
| 15.6" | 39.62 cm | Laptop |
| 24" | 60.96 cm | Monitor |
| 27" | 68.58 cm | Monitor |
| 32" | 81.28 cm | Monitor / small TV |
| 43" | 109.22 cm | TV |
| 55" | 139.70 cm | TV |
| 65" | 165.10 cm | Large TV |
Inches to centimeters: 1–12 inch table
| Inches | Centimeters |
|---|---|
| 1" | 2.54 cm |
| 2" | 5.08 cm |
| 3" | 7.62 cm |
| 4" | 10.16 cm |
| 5" | 12.70 cm |
| 6" | 15.24 cm |
| 7" | 17.78 cm |
| 8" | 20.32 cm |
| 9" | 22.86 cm |
| 10" | 25.40 cm |
| 11" | 27.94 cm |
| 12" | 30.48 cm |
Where this fits in real workflows
Screen diagonals are only one dimension of a device — if you're comparing displays or resizing images to fit them, pixel dimensions matter too. And if you're converting other unit pairs (miles, liters, kilograms, temperatures), the general Unit Converter covers dozens of them in one place.
For distances rather than lengths, the mile ↔ kilometer converter handles road and running conversions.
Frequently Asked Questions
How many cm in an inch?
1 inch = 2.54 cm exactly. This is the official international definition (since 1959), not a rounded value. So 2 inches = 5.08 cm, 10 inches = 25.4 cm, and to convert any measurement just multiply the inches by 2.54.
How do I convert cm back to inches?
Divide by 2.54. For example 30 cm ÷ 2.54 = 11.81 inches. This converter does both directions automatically — type in whichever field matches the number you have.
How big is a 6.1-inch phone screen in cm?
6.1 inches = 15.49 cm, measured diagonally from corner to corner. The screen's actual width and height depend on the aspect ratio: a 6.1" phone at 19.5:9 is roughly 6.7 cm wide and 14.5 cm tall.
Why are screen sizes measured in inches everywhere?
It's an industry convention inherited from the American TV and computer industry. Even countries that use the metric system for everything else quote phone, monitor and TV diagonals in inches, so converting to centimeters is the only way to picture the real physical size.
Is my data stored anywhere?
No. The conversion runs in your browser with JavaScript; nothing you type is sent to a server, stored or logged.