Video Aspect Ratio Guides

A video aspect ratio calculator computes the simplified ratio, decimal ratio, orientation, and total pixel count for any width and height, and back-solves the unlocked dimension when a preset ratio is chosen. Presets are grouped by category: TV and Streaming, Cinema and Film, Ultrawide, Photography and Print, and Square and Vertical, covering ratios such as 16:9, 9:16, 1:1, 4:5, 21:9, 2.39:1, and IMAX, alongside a custom option for any width and height.

Width and height, in pixels, accept whole numbers, decimals such as 1920.5, simple fractions such as 3/4, and mixed numbers such as 5 1/2. A lock-dimension setting decides which value stays fixed when a different preset is chosen: locking width lets height adjust to match the new ratio, and locking height lets width adjust instead.

Decimal ratio is width divided by height. Simplified ratio divides both values by their greatest common divisor to express the ratio in smallest integer form, and Settings can show that GCD derivation step by step. Total pixels equal width multiplied by height, with one megapixel equal to one million pixels; orientation reads as landscape, portrait, or square depending on which dimension is larger. A common-resolutions list surfaces well-known resolutions sharing the current ratio, useful when picking a target for encoding or export, and a quick-reference table summarizes common ratios across film, television, social media, photography, and specialty formats such as IMAX and Ultra Panavision 70.

At the default 1920 by 1080, the greatest common divisor of 1920 and 1080 is 120, so the simplified ratio is 16:9 (1920/120 to 1080/120). The decimal ratio is 1.778 (1920/1080), and total pixels equal 2,073,600 (1920 x 1080), about 2.07 megapixels.

Plan aspect ratios across video production, graphic design, web development, and social media content creation. Choosing the correct ratio ensures content displays properly without unwanted cropping or letterboxing. The scenarios below show where this tool saves time and prevents costly export errors.

• YouTube Creators: An editing timeline matching the standard 16:9 ratio at 1920 by 1080 or 3840 by 2160 keeps the player from showing black bars on export.
• TikTok and Instagram Reels: Short-form content uses 9:16 vertical dimensions, 1080 by 1920; locking width gives the exact height needed when a camera captures at a non-standard resolution.
• Instagram Posts and Portraits: Square posts use 1:1 at 1080 by 1080, and portrait feed posts use 4:5 at 1080 by 1350, maximizing screen real estate in the mobile feed.
• Film and Cinema Production: Theatrical projection deliverables run 2.39:1 anamorphic, 1.85:1 flat widescreen, 1.43:1 IMAX 70mm, or 1.90:1 IMAX Digital, with the common-resolutions list narrowing the right render target for each.
• Web Designers: Hero image and background video dimensions that hold a consistent aspect ratio keep a layout stable across responsive breakpoints.
• Game Developers: Viewport dimensions for ultrawide 21:9 and super ultrawide 32:9 support, with 16:9 and 4:3 fallback modes, cover older displays alongside newer ones.
• Digital Signage: Portrait-mode (9:16, 9:21) or square (1:1) resolutions fit digital displays used in retail, airports, and kiosks.
• Photographers: Converting between 3:2 DSLR output and 4:5 or 1:1 crops required for print and social sharing replaces guessing at pixel counts with exact ones.
• Educators and Presenters: Slide decks and screen recordings matched to the target display ratio, whether 16:9 for modern projectors, 16:10 for laptop screens, or 4:3 for older equipment, avoid stretch or crop at presentation time.