Viewing Distance Calculator — TV & Projector

Free seating-distance calculator that accounts for both screen size and resolution. Unlike most calculators that hard-code a "1.5× width" rule, this one computes the minimum distance below which individual pixels become visible at 20/20 vision (using arc-minute angular acuity), so 4K and 8K screens correctly allow closer seating than 1080p. Outputs THX (26°), SMPTE (30°), 4K-resolvable minimum, and engagement maximum, plus a visual marker showing where your current seat falls.

How to use

1
Enter screen diagonal

Inches for fixed-size screens, centimetres for projection.

2
Pick resolution

1080p = old TVs / cheap projectors. 4K = most modern. 8K = niche, requires very close seating to benefit.

3
Enter your seat distance

See whether you're in the cinema zone, comfort zone, or outside both.

Resolution-aware seating distance — 4K lets you sit closer than 1080p

Your distance vs. recommended zones

Too closeTHXSMPTEToo far

Features

Resolution-aware Four reference zones Visual zone marker
Who is this tool for?
📽️ Projector Owners

FAQ

Why does resolution matter for distance?

Eyes resolve detail at ~1 arc-minute per pixel. A 4K screen has 4× the pixels of 1080p, so you can sit at half the distance before pixels become visible — letting you fill more of your field of view.

Should I aim for THX or SMPTE?

THX (26° viewing angle) is more immersive; SMPTE (30°) is more comfortable for daily viewing. Cinema enthusiasts pick THX, mixed-content viewers pick SMPTE.

What's the formula for the resolution-limited minimum?

min_dist = screen_height / (2 × tan(0.5/60° × resolution_height)). For 4K (2160 lines), this is roughly 1× screen height; for 1080p, roughly 2× screen height.

💡 Want us to improve this tool just for you?

We can — and it's free! Just send us a quick message with your idea. If you'd like to discuss it in detail, leave your email and we'll get back to you. You can stay anonymous.

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