TV Size Distance Calculator

How TV Viewing Distance Is Calculated

The ideal distance between your sofa and TV depends on screen size and the viewing standard you prefer. THX recommends sitting closer for a more immersive cinema feel, while SMPTE suggests a slightly farther distance for comfortable everyday viewing.

Viewing Distance Formulas

$$\text{THX distance (ft)} = \text{screen diagonal (in)} \times 1.2$$ $$\text{SMPTE distance (ft)} = \text{screen diagonal (in)} \times 1.6$$

To find the recommended TV size from your room layout, divide viewing distance by the same multiplier:

$$\text{recommended diagonal (in)} = \frac{\text{viewing distance (ft)}}{\text{multiplier}}$$

Frequently Asked Questions

What is the difference between THX and SMPTE recommendations?

THX targets a wider field of view for home theater immersion, so the recommended distance is shorter (multiply diagonal by 1.2). SMPTE is more conservative for general TV watching (multiply by 1.6).

How far should I sit from a 65-inch TV?

About 78 feet using THX (65 × 1.2) or about 104 feet using SMPTE (65 × 1.6). Room layout and personal preference may shift this slightly.

What TV size fits an 8-foot viewing distance?

THX suggests about a 6.7-inch diagonal (8 ÷ 1.2). SMPTE suggests about a 5-inch diagonal (8 ÷ 1.6).

Do these formulas work for 4K and 8K TVs?

Yes for basic seating distance planning. Higher resolution can support slightly closer viewing before pixel structure becomes visible, but THX and SMPTE remain useful starting points.

Report

How TV Viewing Distance Is Calculated

Viewing Distance Formulas

Frequently Asked Questions

Related Tools

Recent Visits