16 x 9 Ratio Calculator: Find Width and Height

This 16 x 9 ratio calculator finds the matching width or height for a 16:9 image, screen, or video frame. Enter either dimension in the same unit, and it returns the other dimension plus the corresponding diagonal.

Formula

A 16:9 ratio means the width is 16 parts for every 9 parts of height. The equivalent equations are:

Height = width × 9 ÷ 16
Width = height × 16 ÷ 9
Diagonal = √(width² + height²)

Here, w is the entered width and h is the entered height, both in the same unit. The calculator’s “Height from width” uses w × 9 ÷ 16; “Width from height” uses h × 16 ÷ 9. The diagonal is calculated from the entered width and the matching 16:9 height. Outputs use the same unit as the inputs.

Worked Example

Using the defaults, the entered width is 16 units and the entered height is 9 units.

• Height from width: 16 × 9 ÷ 16 = 9.00 units.
• Width from height: 9 × 16 ÷ 9 = 16.00 units.
• Diagonal: √(16² + 9²) = √337 ≈ 18.36 units.

The matching dimensions are 16 by 9, and their diagonal is about 18.36 in the same unit. The displayed results are rounded to two decimal places.

What a 16:9 Ratio Means

The numbers describe a proportion, not a required size or measurement unit. A frame that is 16 inches wide and 9 inches high has the same shape as one that is 1920 pixels wide and 1080 pixels high: both reduce to 16:9. The calculator preserves that shape while scaling the dimensions.

16:9 is commonly used for widescreen video, displays, presentation canvases, and image crops. It is a landscape ratio when the longer dimension is horizontal; turning the frame gives the portrait orientation 9:16. The ratio alone does not determine resolution, sharpness, physical screen size, or whether a particular platform accepts a file.

How to Use the Calculator

Enter the width and height you know. To calculate a matching height, use the width field; to calculate a matching width, use the height field. The result fields show both conversions and the diagonal based on the entered width.

For example, if a design is 1280 pixels wide, enter 1280 as the width. The height result is 720 pixels. If instead you have a 30-centimeter height, enter 30 as the height to get a corresponding width of about 53.33 centimeters. Do not mix pixels with centimeters or inches in the two inputs: the ratio calculation assumes both values use the same unit.

How to Choose

Start with the dimension that is fixed by your project. If a display or export requires a particular width, enter that width and use the calculated height; if a print layout or crop has a fixed height, work from the height. Keep the unit consistent and retain the unrounded value for further calculations when precision matters.

Check whether you need a landscape 16:9 frame or a portrait 9:16 frame. For portrait work, swap the roles of width and height rather than treating 16:9 as a portrait proportion. Also distinguish the diagonal from width: display sizes are often described by diagonal, but a diagonal alone does not tell you the physical width and height unless the aspect ratio is known.

Finally, check the destination’s required pixel dimensions and any crop or safe-area requirements separately. A correct ratio does not guarantee that an image will fit without cropping, that its resolution is sufficient, or that important text will remain visible across devices.

Common Mistakes and Limits

One frequent error is reversing the multiplier. Height is width × 9 ÷ 16, not width × 16 ÷ 9; the latter calculates width from a known height. Another is rounding too early. Keep more precision during intermediate steps, then round the final dimensions to the whole pixels or measurement increment your project requires.

The calculator assumes an exact 16:9 ratio and straight, rectangular dimensions. It does not account for borders, bezels, margins, printer bleed, pixel aspect ratio, or content that must be cropped. Some devices and media formats use nearby but different dimensions, so verify the actual specification when matching an existing file or screen.

Frequently Asked Questions

What is the formula for a 16:9 width and height?
Height equals width × 9 ÷ 16. Width equals height × 16 ÷ 9.

What is 16:9 in pixels?
There is no single pixel size. Common examples include 1280 × 720 and 1920 × 1080; both have a 16:9 ratio.

Is 1920 × 1080 a 16:9 resolution?
Yes. Dividing both dimensions by 120 reduces 1920:1080 to 16:9.

How do I convert a 16:9 frame to portrait?
Swap the dimensions to make the proportion 9:16. For example, 1080 × 1920 is portrait 9:16.

Can I use inches, centimeters, or pixels?
Yes. Use any unit, but enter both dimensions in that same unit. The output stays in the unit you entered.

Does the diagonal tell me the screen width?
Not by itself. You also need the aspect ratio; with a 16:9 ratio, width and height can be derived from the diagonal, but this calculator reports the diagonal from a width-based calculation.

Final Thoughts

Use the 16 x 9 ratio calculator to scale a frame without changing its shape. Enter a known width or height, keep units consistent, and confirm the required dimensions with the destination before exporting or printing.

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in w | Width | units | 16 | 0
in h | Height | units | 9 | 0
out h2 | Height from width | units | w * 9 / 16 | 2
out w2 | Width from height | units | h * 16 / 9 | 2
out d | Diagonal | units | sqrt(w^2 + (w * 9 / 16)^2) | 2