Aspect Ratio Calculator

Calculate, convert & visualize aspect ratios for video, images and displays

Aspect Ratio Calculator

Calculate & convert ratios for video, images and displays

Dimensions
Width
Height

Aspect Ratio

Quick Ratios
Precision:
100% Private - Runs locally in your browser

How to Use

  1. 1 Enter width and height to calculate the aspect ratio
  2. 2 Or select a platform preset (YouTube, Instagram, TikTok)
  3. 3 Use "Lock Ratio" to resize while maintaining proportions
  4. 4 Copy the dimensions or ratio for your project
  5. 5 View the visual preview to see the proportion

What You Get

Instant aspect ratio calculator that converts between width/height and ratio formats. Includes presets for YouTube (16:9), Instagram (1:1, 4:5, 9:16), TikTok (9:16), Twitter, and cinema formats. Visual preview shows proportions in real-time.

Input: 1920 × 1080

Output: 16:9 (1.778:1)

Input: 1080 × 1350

Output: 4:5 (Instagram Portrait)

Input: 16:9 + Width: 1280

Output: Height: 720

What is aspect ratio?

Aspect ratio is the proportional relationship between width and height of an image or video. It's expressed as two numbers separated by a colon (e.g., 16:9). A 16:9 ratio means for every 16 units of width, there are 9 units of height.

What aspect ratio does YouTube use?

YouTube uses 16:9 as the standard aspect ratio. The recommended resolution is 1920×1080 (1080p) or higher like 3840×2160 (4K). YouTube Shorts use 9:16 vertical format at 1080×1920.

What is the best aspect ratio for Instagram?

Instagram supports multiple ratios: Square posts (1:1) at 1080×1080, Portrait posts (4:5) at 1080×1350 for maximum feed visibility, Stories and Reels (9:16) at 1080×1920, and Landscape (1.91:1) at 1080×566.

What aspect ratio is TikTok?

TikTok uses 9:16 vertical aspect ratio. The recommended resolution is 1080×1920 pixels. This maximizes screen space on mobile devices and creates an immersive viewing experience.

How do I calculate aspect ratio from dimensions?

Divide both width and height by their Greatest Common Divisor (GCD). For example, 1920÷120 = 16 and 1080÷120 = 9, giving you 16:9. Our calculator does this automatically.

What is 16:9 in pixels?

Common 16:9 resolutions: 1920×1080 (Full HD), 2560×1440 (2K/QHD), 3840×2160 (4K UHD), 1280×720 (HD). Any dimensions where width÷height = 1.778 are 16:9.

What is 4:3 aspect ratio used for?

4:3 was the standard for old TVs and monitors. It's still used for some presentations, older photos, and certain professional video formats. Common resolutions: 1024×768, 1600×1200.

How do I resize without changing aspect ratio?

Lock the aspect ratio and change only one dimension (width or height). The other dimension will be calculated automatically to maintain the same proportions.

100% client-side processing. Your dimensions and calculations never leave your device.