Everyday calculator
Screen Size Calculator, Dimensions, Aspect Ratio & PPI
Calculate screen width, height, and pixel density (PPI) from diagonal size and resolution. Compare aspect ratios and find ideal viewing distances.
How CalcMesh computes screen dimensions
A screen’s width and height come from its diagonal and aspect ratio by the Pythagorean theorem; a 27-inch 16:9 display, for instance, is about 23.5 inches wide and 13.2 inches tall.
We also derive pixel density (PPI) from the resolution you enter; the geometry we use is documented in our methodology.
Screen Size Guide
Common Screen Sizes
| Device | Size | Resolution |
|---|---|---|
| Smartphone | 6.1-6.7" | 1080x2400 |
| Tablet | 10-13" | 2560x1600 |
| Laptop | 13-16" | 1920x1200 |
| Monitor | 24-32" | 2560x1440 |
| TV | 55-75" | 3840x2160 |
Understanding PPI
Pixels Per Inch (PPI) determines how sharp a display looks. The ideal PPI depends on viewing distance:
- Phones (8-12"): 300+ PPI for crisp text
- Tablets (18-24"): 200-270 PPI
- Monitors (24-36"): 90-160 PPI
- TVs (6-12 ft): 40-80 PPI is fine
Viewing Distance
A common recommendation is to sit at a distance of 1.5 to 2.5 times the screen diagonal. For a 27-inch monitor, that means roughly 40 to 68 inches (3.3 to 5.6 feet) away. Sitting too close to a large screen can cause eye strain, while sitting too far reduces the immersive benefit.
Note: Screen measurements refer to the viewable display area, not including bezels or casing.
Methodology & Assumptions
This calculator implements standard formulas drawn from primary-source authorities. Values are point-in-time estimates; consult a licensed professional for high-stakes decisions. See the per-input definitions and source citations below.
How this works
Computations are deterministic and run client-side, no inputs leave your
browser. Formulas are derived from
standard published formulas for the calculator's domain (mortgage,
taxes, energy, conversions, etc.). When the underlying agency publishes
updated rates or thresholds we refresh defaults and update the page's
lastmod timestamp.
| Input | Default | Source / authority |
|---|---|---|
| All inputs | Domain-typical defaults | Editorial methodology, CalcMesh 2026 |