TV or projector — the math behind the right call for your room
The room decides this, not the spec sheet. A projector in a bright living room with two windows looks washed-out next to a 65-inch QD-OLED at half the cost. In a blacked-out dedicated theater, a $3,000 projector buys you a 120-inch image that no consumer TV touches.
This calculator compares cost-per-inch and 5-year total cost of ownership for a TV and a projector sized to your room and use case, factoring in your actual lamp life, electricity rate, and viewing hours. It outputs a year-by-year cost curve plus a screen-size sanity check against your seating distance.
Use this when you're stuck between an 85-inch TV ($2,500) and a 120-inch projector setup ($3,500-$5,000 all-in) and need numbers, not vibes.
How the TV vs Projector Comparison Works
The Formula
Cost-per-inch: total_price / screen_diagonal_inches. 5-year TCO: upfront + (lamp_replacements x lamp_price) + (electricity_kWh x rate x 5). Lamp replacements over 5 years: floor(hours_per_year x 5 / lamp_life_hours). The screen-size sanity check enforces the SMPTE 30-degree minimum at your seating distance: min_screen_inches = 2 x distance_ft x tan(15 degrees) x 12 / 0.872 (last term converts width to 16:9 diagonal).
Worked Example
85-inch TV: $2,500, 150 W draw. 120-inch projector setup: $1,500 projector + $1,500 screen + AVR/install = $4,000 total, 300 W draw, $80 lamps every 3,500 hours. 15 hours/week = 780 hours/year. Electricity at $0.17/kWh. TV 5-year electricity: 150 W x 780 h x 5 / 1000 x $0.17 = $99.45. TV 5-year TCO: $2,599.45 ($30.58/inch). Projector lamps over 5 years: floor(3,900 / 3,500) = 1 replacement = $80. Projector electricity: 300 W x 780 h x 5 / 1000 x $0.17 = $198.90. Projector 5-year TCO: $4,278.90 ($35.66/inch). Cost-per-inch is closer than the upfront prices suggest, and a laser projector eliminates the lamp line entirely.
Standards
SMPTE 30-degree viewing angle minimum drives the screen-size floor at any seating distance. ANSI lumens for ambient-light tolerance: ~2,500 lumens for dark rooms, 3,500+ for mixed-light, 4,500+ for living rooms with daylight (and even that often loses to a bright TV). The TCO model uses standard-mode lamp life; halve electricity draw and multiply lamp life by ~1.4x for eco mode if applicable.
Limitations
The calculator doesn't price installation labor, in-wall wiring, or sound treatment — projector installs typically add $300-1,500 for a clean ceiling mount with a long HDMI run. Image quality differences (HDR brightness, black level, motion handling) aren't quantified; a 4,000-nit Mini-LED in a dark room can outperform a $3,000 projector on punch even at a smaller screen size. The 5-year window also misses laser projectors that don't have lamp costs — set lamp price to $0 and lamp life to 20,000+ hours to model a laser unit.
