Calculate and simplify aspect ratios, and resize dimensions while maintaining the aspect ratio. Essential for video, photography, and display design.
Simplified Ratio
16:9
Decimal Ratio
1.7778
Original
1920 × 1080
Aspect ratio is the proportional relationship between the width and height of an image, video, or display. Expressed as a ratio (e.g., 16:9), it describes how wide something is relative to its height. A higher first number means a wider format, while a higher second number indicates a taller format.
Common aspect ratios include 16:9 (widescreen TVs and monitors), 4:3 (traditional video), 21:9 (ultrawide), and 1:1 (square, common on social media). Understanding aspect ratios is crucial for photographers, videographers, designers, and anyone working with visual media.
When you simplify an aspect ratio, you're reducing it to its lowest terms using the greatest common divisor (GCD). For example, 1920×1080 simplifies to 16:9 because GCD(1920, 1080) = 120, and 1920÷120 = 16, 1080÷120 = 9.
⚠ Note on Decimal Dimensions
Decimal input dimensions are rounded to the nearest integer before calculating the simplified ratio. This is appropriate for pixel-based workflows (video, photography, displays). For precise mathematical aspect ratios with fractional dimensions, enter exact integer values.
Example 1: Simplify 1920×1080
Step 1: Find GCD(1920, 1080)
GCD = 120
Step 2: Divide both by GCD
1920 ÷ 120 = 16 | 1080 ÷ 120 = 9
Result: 16:9 aspect ratio
Example 2: Resize 1920 width to 1280 maintaining 16:9
Original: 1920 × 1080 (16:9 ratio)
New width: 1280
Calculate: New Height = (1280 × 1080) ÷ 1920 = 720
Result: 1280 × 720 maintains 16:9 ratio
It means for every 16 units of width, there are 9 units of height. It's the standard widescreen format for modern TVs, monitors, and HD video.
Yes, 1920×1080 simplifies to 16:9. The 1920×1080 is a specific resolution, while 16:9 is the aspect ratio both share.
They ensure content displays correctly without stretching or distorting. Mismatched ratios can make people look thin or fat, or cause black bars around images.
16:9 is the modern standard for TVs, monitors, and video. 4:3 was traditional, and 16:10 is common for computer monitors.
You can crop it (reduces one dimension), stretch it (distorts image), or add padding. Cropping with maintained ratio preserves image quality.
A 1:1 aspect ratio, where width equals height. Common for profile pictures, album art, and Instagram posts.
Use the Euclidean algorithm: repeatedly replace the larger number with (larger mod smaller) until remainder is 0. The final non-zero value is the GCD.
The decimal ratio (width÷height) is useful for calculations and comparisons. For example, 16:9 ≈ 1.7778, showing width is 1.78 times the height.
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