The Challenge
Phone screens are measured in inches diagonally, but the number tells you almost nothing about how the phone actually feels in your hand. A 6.7-inch phone is 17.02cm diagonally — but whether it fits your palm depends on width, which varies by aspect ratio. Modern phones use tall 19.5:9 or 20:9 ratios, making them narrower than older 16:9 phones of the same screen size. A 6.1-inch iPhone 15 is 15.49cm diagonal, 7.15cm wide. A 6.1-inch Android with a 20:9 ratio is the same diagonal but only 6.8cm wide. Same inch number, different phone. Multiply screen inches by 2.54 for the diagonal in cm, then check width separately — that's what determines one-handed usability.
Phone Screen Size Chart: Inches to Centimeters
| Screen (inches) | Diagonal (cm) | Width 20:9 (cm) | Height 20:9 (cm) |
|---|---|---|---|
| 5.4 in | 13.72 cm | 6.05 cm | 13.56 cm |
| 6.0 in | 15.24 cm | 6.72 cm | 15.07 cm |
| 6.1 in | 15.49 cm | 6.83 cm | 15.31 cm |
| 6.2 in | 15.75 cm | 6.94 cm | 15.56 cm |
| 6.3 in | 16.00 cm | 7.06 cm | 15.81 cm |
| 6.4 in | 16.26 cm | 7.17 cm | 16.07 cm |
| 6.5 in | 16.51 cm | 7.28 cm | 16.32 cm |
| 6.6 in | 16.76 cm | 7.39 cm | 16.57 cm |
| 6.7 in | 17.02 cm | 7.50 cm | 16.82 cm |
| 6.8 in | 17.27 cm | 7.62 cm | 17.07 cm |
| 6.9 in | 17.53 cm | 7.73 cm | 17.33 cm |
| 7.0 in | 17.78 cm | 7.84 cm | 17.58 cm |
| 7.6 in | 19.30 cm | 8.51 cm | 19.07 cm |
| 8.3 in | 21.08 cm | 9.30 cm | 20.84 cm |
Major Smartphone Screen Sizes in Centimeters (2024)
| Phone Model | Screen (inches) | Diagonal (cm) | Physical Width (cm) |
|---|---|---|---|
| iPhone 15 | 6.1 in | 15.49 cm | 7.15 cm |
| iPhone 15 Plus | 6.7 in | 17.02 cm | 7.77 cm |
| iPhone 15 Pro | 6.1 in | 15.49 cm | 7.09 cm |
| iPhone 15 Pro Max | 6.7 in | 17.02 cm | 7.69 cm |
| Samsung Galaxy S24 | 6.2 in | 15.75 cm | 7.06 cm |
| Samsung Galaxy S24+ | 6.7 in | 17.02 cm | 7.58 cm |
| Samsung Galaxy S24 Ultra | 6.8 in | 17.27 cm | 7.92 cm |
| Google Pixel 9 | 6.3 in | 16.00 cm | 7.27 cm |
| Google Pixel 9 Pro XL | 6.8 in | 17.27 cm | 7.68 cm |
| OnePlus 12 | 6.82 in | 17.32 cm | 7.39 cm |
| Samsung Galaxy Z Fold 6 (open) | 7.6 in | 19.30 cm | 13.26 cm |
| Samsung Galaxy Z Flip 6 (open) | 6.7 in | 17.02 cm | 7.13 cm |
Why the Same Screen Size Feels Different Across Phones
A 6.7-inch screen on a Samsung Galaxy S24+ and a 6.7-inch screen on an iPhone 15 Plus measure the same diagonal — 17.02cm — but the phones feel different in hand. The S24+ is 15.8cm tall and 7.58cm wide. The iPhone 15 Plus is 16.0cm tall and 7.77cm wide. Same diagonal, different proportions. Aspect ratio is the variable: Samsung uses 19.5:9, Apple uses 19.5:9 too in this case, but chassis design, corner radius, and bezel width all shift the physical feel. The diagonal in cm gives you a display area comparison. Physical dimensions — always listed in millimeters in the spec sheet — tell you whether the phone fits your hand or pocket.
How to Find a Phone's Real Physical Size from Screen Inches
- Multiply screen inches by 2.54 to get diagonal in cm — this is display area only
- Find the phone's aspect ratio in the spec sheet (common: 19.5:9, 20:9, 21:9)
- Calculate screen width: diagonal ÷ √(ratio_height² + ratio_width²) × ratio_width
- Add bezel width (typically 0.3–0.8cm per side on modern phones) to get physical body width
- For a quick check: manufacturer spec sheets always list physical dimensions in mm — use those directly
Screen Size vs Physical Size: What Each Tells You
Choosing a Phone by Screen Size: What to Actually Check
- Convert the screen diagonal to cm to compare across brands on equal terms
- Check physical width in mm — under 72mm is generally one-hand friendly, over 77mm is two-hand territory
- Aspect ratio affects content: 20:9 is better for video; wider ratios show more of websites and documents
- Foldable phones list the unfolded screen size — the folded outer display is a separate, smaller screen
- For accessibility needs, screen size alone is insufficient — check display scaling options and minimum touch target sizes
Step-by-Step Workflow
Enter your phone's screen size in inches — found in spec sheet or box
Diagonal in centimeters appears instantly
Cross-reference with the width chart below for real-world size feel
Specifications
- Formula
- cm = inches × 2.54
- 6.1-inch screen
- 15.49 cm diagonal
- 6.7-inch screen
- 17.02 cm diagonal
- 6.8-inch screen
- 17.27 cm diagonal
- Common ratio (2024)
- 19.5:9 to 21:9
- Width estimate (20:9)
- diagonal × 0.441
- Width estimate (19.5:9)
- diagonal × 0.450
Best Practices
- Screen diagonal in cm tells you display area — screen width tells you pocket and hand fit
- Most Android flagships in 2024 use 19.5:9 or 20:9; iPhones use 19.5:9
- Compact phones: under 6.1in (15.5cm). Standard: 6.1–6.4in. Large: 6.5–6.7in. Max/Ultra: 6.7in+
- Foldable screens: listed size is unfolded diagonal — folded outer screen is always smaller
- Case sizing uses physical phone dimensions, not screen size — always check mm width and height
Frequently Asked Questions
How big is a 6.7-inch phone screen in centimeters?
6.7 inches × 2.54 = 17.02cm diagonal. On a 20:9 phone, screen width is about 7.5cm and height about 16.7cm. Physical phone body will be slightly larger — typically 7.5–7.8cm wide and 16.3–16.5cm tall including bezels.
How big is the iPhone 15 screen in centimeters?
iPhone 15 has a 6.1-inch screen: 6.1 × 2.54 = 15.49cm diagonal. The physical phone is 14.76cm tall and 7.15cm wide. iPhone 15 Plus is 6.7 inches = 17.02cm diagonal, with a physical body 16.0cm tall and 7.77cm wide.
What phone screen size is 16cm?
16cm ÷ 2.54 = 6.30 inches. Phones in the 6.2–6.4 inch range have diagonals near 16cm. The Samsung Galaxy S24 (6.2in = 15.75cm) and S24+ (6.7in = 17.02cm) bracket this size. Most 'standard' flagship phones fall in the 15.5–16.5cm diagonal range.
Does a larger screen diagonal mean a wider phone?
Not always. Aspect ratio determines width more than diagonal does. A 6.7-inch 20:9 phone is narrower than a 6.7-inch 16:9 phone would be. Manufacturers have stretched screens taller rather than wider since 2018, keeping phones pocketable while growing screen area. Always check physical width in mm from the spec sheet.
How do I compare phone screen sizes from different brands?
Convert all screens to cm diagonal for a common baseline, then compare aspect ratios. Two phones with identical diagonal but different ratios (say 19.5:9 vs 21:9) have the same diagonal but the 21:9 phone is narrower and taller. For content consumption — video, games — diagonal matters. For typing and reach — width matters.
What is the screen size of common tablets in centimeters?
iPad mini (8.3in) = 21.08cm. iPad 10th gen (10.9in) = 27.69cm. iPad Air (11in) = 27.94cm. iPad Pro 12.9in = 32.77cm. Samsung Galaxy Tab S9 (11in) = 27.94cm. Tab S9 Ultra (14.6in) = 37.08cm. Tablets use 4:3 or 16:10 ratios, so they are proportionally wider than phones at the same diagonal.
Why do phone manufacturers still use inches for screen size?
It started with the US market and TV industry conventions, and the display supply chain — largely driven by US and Japanese companies in its early decades — standardized on inches. The practice stuck globally even as metric became dominant elsewhere. Today it persists because comparison shopping is built around inch figures: consumers know what a 6.7-inch phone feels like, and changing the unit would break that intuition.