Screen Size Calculator – Diagonal, Width, Height

Calculate screen dimensions from diagonal size and aspect ratio.

About This Calculator

Calculate screen dimensions from diagonal size and aspect ratio. Use the calculator above for instant results.

Worked Examples

Example 1: 27" at 16:9

  • Width: 23.53" | Height: 13.24" | Area: 311.6 sq in

Answer: 23.53" × 13.24"

Example 2: 55" TV at 16:9

  • Width: 47.95" | Height: 26.97"

Answer: 47.95" × 26.97"

Example 3: 24" at 16:10

  • Width: 20.33" | Height: 12.71"

Answer: 20.33" × 12.71"

Who Uses This Calculator?

💻
PC Builders

Check monitor dimensions before buying.

📺
TV Buyers

Understand TV physical dimensions.

🏫
Presenters

Plan projector screen sizing.

📊
IT Teams

Spec workstation displays.

Common Mistakes to Avoid

❌ Diagonal doesn't tell you width

A 27" 16:9 monitor is 23.5" wide. A 27" 21:9 ultrawide is 25.1" wide. Aspect ratio changes physical dimensions significantly.

❌ Curved vs flat area

Same diagonal size on curved screens has slightly different viewing angles. The area formula is the same.

Frequently Asked Questions

Common aspect ratios?

16:9 (most monitors/TVs). 21:9 (ultrawide). 32:9 (super ultrawide). 4:3 (old standard). 16:10 (some laptops/monitors).

TV size guide?

Living room 10-12ft away: 55-65". Bedroom 6-8ft: 40-50". Monitor desk use: 24-32".

Physical size vs resolution?

A 27" 4K monitor has the same physical size as a 27" 1080p monitor but 4× more pixels.