Video Aspect Ratios Explained: 16:9, 4:3, 9:16 and When to Use Each
Choosing the wrong aspect ratio means black bars, awkward cropping, or a video that looks amateur.
Aspect ratio is the proportional relationship between width and height. 16:9 (widescreen) is the standard for YouTube, TV, and most video content. 9:16 (vertical) is for TikTok, Instagram Reels, and YouTube Shorts. 1:1 (square) is for Instagram feed posts. 4:3 is the old TV format, rarely used today except for some presentations.
Common Resolutions by Aspect Ratio
16:9 — 1920×1080 (1080p), 3840×2160 (4K), 1280×720 (720p). 9:16 — 1080×1920 (vertical 1080p). 1:1 — 1080×1080. 4:3 — 1024×768. 21:9 — 2560×1080 (ultrawide).
When to Use Each
YouTube videos: always 16:9. Instagram Reels/TikTok: always 9:16. Instagram feed: 1:1 or 4:5 (portrait). LinkedIn video: 16:9 or 1:1. Film/cinema: 2.39:1 (ultra-widescreen). Presentations: 16:9 (modern) or 4:3 (legacy projectors).