Calculate the perfect distance between your seat and your TV based on screen size and resolution.
1080p (Full HD)
4K (Ultra HD)
8K (Extreme HD)
THX Recommended (40° View):–
SMPTE Recommended (30° View):–
Visual Acuity Distance (Ideal for Detail):–
Optimal TV Viewing Distance: The Ultimate Guide
Finding the right viewing distance for your home theater isn't just about comfort; it's about science. If you sit too far away, you lose the benefit of high-resolution 4K or 8K pixels. If you sit too close, your eyes will strain, and you may notice the individual pixel structure of the screen.
Understanding THX and SMPTE Standards
Professional cinematic standards help define the "Immersive Experience":
THX Standard: Recommends a 40-degree field of view. This is considered the "Cinema" sweet spot where the screen fills your primary field of vision for maximum immersion.
SMPTE Standard: The Society of Motion Picture and Television Engineers suggests a 30-degree field of view. This is often better for general TV watching, sports, and news.
Resolution and Visual Acuity
The "Visual Acuity" distance is the point where a person with 20/20 vision can no longer distinguish individual pixels. For a 65-inch 4K TV, this is approximately 4.3 feet. If you sit further than 9 feet from a 65-inch 4K TV, your eyes can't actually see the difference between 4K and 1080p!
Quick Reference Table (4K Resolution)
Screen Size
THX (Immersive)
SMPTE (Standard)
55″
5.5 ft
7.5 ft
65″
6.5 ft
8.9 ft
75″
7.5 ft
10.2 ft
85″
8.5 ft
11.6 ft
Realistic Example: The 65-Inch Dilemma
If you have a 65-inch 4K TV in a living room where your couch is 12 feet away, you are actually sitting too far to appreciate the 4K resolution. To get the full 4K experience, you should move your seating to roughly 6.5 to 8 feet away. This calculator uses standard trigonometric formulas to ensure you get the best seat in the house.
function calculateHTDistance() {
var screenSize = document.getElementById('ht_screenSize').value;
var resolution = document.getElementById('ht_resolution').value;
var resultsDiv = document.getElementById('ht_results');
if (screenSize === "" || screenSize <= 0) {
alert("Please enter a valid screen size.");
return;
}
var size = parseFloat(screenSize);
// THX Formula: Distance = Screen Size / 0.835
// Result in inches, converted to feet
var thxInches = size / 0.84;
var thxFeet = (thxInches / 12).toFixed(1);
// SMPTE Formula: Distance = Screen Size / 0.6
var smpteInches = size / 0.625;
var smpteFeet = (smpteInches / 12).toFixed(1);
// Visual Acuity distance (Simplified industry multipliers)
// 1080p: ~1.5 – 2.5x screen size
// 4K: ~1.0 – 1.5x screen size
// 8K: ~0.5 – 1.0x screen size
var acuityMultiplier;
if (resolution == "1080") {
acuityMultiplier = 1.6;
} else if (resolution == "4000") {
acuityMultiplier = 1.1;
} else {
acuityMultiplier = 0.7;
}
var acuityFeet = ((size * acuityMultiplier) / 12).toFixed(1);
// Update Display
document.getElementById('res_thx').innerHTML = thxFeet + " feet (" + Math.round(thxFeet * 30.48) + " cm)";
document.getElementById('res_smpte').innerHTML = smpteFeet + " feet (" + Math.round(smpteFeet * 30.48) + " cm)";
document.getElementById('res_acuity').innerHTML = acuityFeet + " feet (" + Math.round(acuityFeet * 30.48) + " cm)";
// Show results
resultsDiv.style.display = 'block';
}