Aspect Ratio Calculator
Find the simplified ratio for any resolution, or scale dimensions proportionally. Perfect for video, images, and screen design.
Select a common preset or enter a custom ratio, then enter one dimension to calculate the other.
| Ratio | Decimal | Common Uses | Examples |
|---|---|---|---|
| 16:9 | 1.778 | Video Display | 1080p, 4K, YouTube |
| 4:3 | 1.333 | Legacy Photo | Old TV, iPad |
| 21:9 | 2.333 | Ultrawide Cinema | Ultrawide monitors |
| 1:1 | 1.000 | Social | Instagram, Profile pics |
| 9:16 | 0.563 | Mobile Stories | TikTok, Reels, Stories |
| 3:2 | 1.500 | Photo Print | DSLR, 35mm film |
| 5:4 | 1.250 | Print Display | 5×4 prints, old monitors |
| 2:1 | 2.000 | Cinema | Netflix originals |
| 2:3 | 0.667 | Portrait Print | Portrait photography |
| 4:5 | 0.800 | Social | Instagram portrait posts |
| 1.85:1 | 1.850 | Cinema | US theatrical standard |
| 2.39:1 | 2.390 | Cinema | Anamorphic widescreen |
How to Calculate Aspect Ratios Online
ToolsPix Aspect Ratio Calculator lets you find the simplified ratio for any resolution and scale dimensions proportionally — entirely in your browser. There is no software to install, no account to create, and no need to upload files to any server.
Why use ToolsPix Aspect Ratio Calculator?
- Completely free with no limits on calculations or resolutions.
- All calculations happen locally in the browser — no data is sent anywhere.
- Works on Windows, Mac, Linux, iPhone, and Android — anywhere with a modern browser.
- Supports common presets for video, social media, print, and cinema formats.
- No watermarks, no sign-up, and no third-party trackers.
Steps to find your aspect ratio
Select the Find Ratio tab and enter your width and height values. The calculator instantly displays the simplified ratio, decimal equivalent, and megapixel count. To scale dimensions, switch to the Scale Dimensions tab, choose a preset or enter a custom ratio, then type one dimension to calculate the other automatically. Once the page is loaded, the tool also works completely offline.
FAQ
What is an aspect ratio?
An aspect ratio describes the proportional relationship between width and height, expressed as two numbers separated by a colon — for example, 16:9. It tells you how wide an image or screen is relative to its height, and helps maintain visual consistency when resizing content.
How does the calculator simplify ratios?
It uses the Greatest Common Divisor (GCD) algorithm to reduce the width and height to their smallest whole-number form. For example, 1920x1080 shares a GCD of 120, so it simplifies to 16:9.
Why does 1920x1080 give 16:9?
Because dividing 1920 and 1080 by their GCD of 120 gives 16 and 9. Any resolution following the 16:9 ratio — like 1280x720 or 3840x2160 — will also simplify to 16:9.
Can I use this for social media image sizes?
Yes. Use the Scale Dimensions tab to find the correct width or height for any platform. Enter the target ratio — for example, 9:16 for Instagram Stories — and one dimension to calculate the other automatically.
Does this tool store or upload my data?
No. All calculations run entirely in your browser using JavaScript. No data is sent to any server, and nothing is collected or stored.