Retro Aspect Ratio Calculator
Calculate native aspect ratios, integer scale factors, and pixel dimensions for retro game resolutions on modern displays.
Why Integer Scaling Matters for Retro Games
What is integer scaling? Integer scaling means each original pixel is displayed as an exact multiple of pixels on your screen — 2x2, 3x3, 4x4, etc. Every original pixel maps cleanly to a grid of identical screen pixels, preserving sharp, square pixel art.
Why not just stretch to fill the screen? Non-integer scaling creates sub-pixel interpolation — some pixels become slightly wider or taller than others. This blurs pixel art, creates uneven grid lines, and makes the image look "off" even with sharp bilinear filtering. On a CRT, this was never an issue since the electron beam naturally blended pixels.
Pixel aspect ratio vs display aspect ratio: Many retro consoles used non-square pixels. The SNES output 256x224 pixels but was designed to display at 4:3 (roughly 8:7 native pixel AR). On a 4:3 monitor, pixels were naturally stretched horizontally. On modern 16:9 displays, you must choose: strict integer scale (slightly pillarboxed, but pixel-perfect) or 4:3 stretch (correct aspect ratio, but non-integer scaling).
Practical recommendation: For pixel art preservation, use the largest integer scale that fits your display. Most emulators like RetroArch, bsnes, and mGBA have a "integer scale" checkbox. For 4:3 games on a 27" 1080p monitor, 3x or 4x integer scale is typically the sweet spot.