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Screen Resolution, PPI & Aspect Ratio Calculator

Built by Kevin Glover · @gloverbuilds · Verified formula

Calculate pixels per inch (PPI), aspect ratio, and total pixel count from screen resolution and size.

📅 Updated April 2026 ✅ Formula verified 📖 4 min read 🆓 Free · No sign-up

In this article

Understanding PPI (Pixels Per Inch)
Common Resolutions

O PPI

PPI = √(largura² + altura²) ÷ diagonal. iPhone 15: 460 PPI. MacBook Pro 14": 254 PPI. TV 65" 4K: 68 PPI. O olho não distingue pixels acima de ~300 PPI em distância de leitura.

Proporções

16:9: padrão TV/monitor. 16:10: produtividade. 21:9: ultrawide. 4:3: antigo. Para trabalho: 16:10 é ideal (mais altura vertical para documentos).

⚡ CalcWolf Insight

The human eye can perceive approximately 300 PPI at 12 inches viewing distance — this is why Apple chose 326 PPI for the original Retina iPhone. At typical desktop viewing distances (24-30 inches), the equivalent is about 100-120 PPI. Buying a 5K monitor for a desktop you sit 3 feet from provides diminishing returns beyond bragging rights.

Frequently asked questions

Bom PPI?▾

Smartphone: 300+. Notebook: 200+. Monitor: 100-120. TV a distância: 60-80 basta.

4K vale a pena?▾

Monitor 27": sim. TV 55" a 3 m: diferença quase imperceptível vs 1080p.

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Kevin Glover · @gloverbuilds

Founder, CalcWolf · GLVTS · Blickr

All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →