Build your Aspect Ratio Calculator with AI in under 5 minutes

Build an aspect ratio calculator that finds the ratio of any width and height, resizes dimensions while keeping the ratio, and previews the shape — with presets like 16:9 and 4:3. Everything runs in the browser.

How it works

Step 1

Describe your idea

Write a plain-text prompt describing what you want.

Step 2

AI builds it

FloopFloop generates production-ready code instantly.

Step 3

Deploy & go live

Your project is hosted on its own subdomain in minutes.

Why build with AI instead of hiring a developer?

	FloopFloop	Traditional developer
Time to launch	Under 5 minutes	2-8 weeks
Cost	From $0	$5,000 - $50,000+
Maintenance	Included	Ongoing retainer

What is a aspect ratio calculator?

An aspect ratio calculator answers two everyday questions for anyone who works with images, video, or layouts: what's the ratio of this size, and what's the matching dimension if I resize it? Give it a width and height and it reduces them to the simplest ratio — 1920×1080 is 16:9 — and shows the decimal too. Lock the ratio and it becomes a proportional resizer: type a new width and it fills in the height that keeps the picture from stretching. Designers, video editors, and front-end developers reach for this constantly — sizing a thumbnail, fitting a hero image, picking an export resolution, or matching a social platform's frame. The maths is simple but fiddly to do by hand (it hinges on the greatest common divisor), and the genuinely useful versions show a live preview of the frame and offer the common presets — 16:9 for widescreen, 9:16 for vertical, 1:1 for square, 4:3 for classic.

Common features

Simplified ratio from any width × height (via GCD)
The decimal ratio (16:9 ≈ 1.78)
A ratio lock for proportional resize
Fill the matching dimension when you change the other
A live preview frame in the current ratio
Preset chips: 16:9, 4:3, 21:9, 1:1, 9:16, 3:2, 2:1, 5:4
Active-preset highlighting
Exact reduction (a 21:9 ultrawide shows as 64:27)
Everything client-side; size remembered on the device
Light and dark themes

Real-world examples

Resizing a thumbnail

A designer locks 16:9, types a new width of 480, and instantly gets a height of 270 — no stretching, no calculator.

Picking a social format

Someone taps the 9:16 preset to size a vertical story, then the 1:1 preset to compare a square crop in the live preview.

Identifying a ratio

A developer pastes 2560×1080 and learns the monitor is actually 64:27 — the exact form of the '21:9' marketing label.

Why FloopFloop fits aspect ratio calculator projects

An aspect ratio tool is a tiny utility you want instant, ad-free, and yours. FloopFloop ships the calculator you want — the presets you use, a pixel-to-print mode, your own brand frame sizes — on your own domain, with all the math running in the browser. The clean 'viewport' that ships by default shows a live preview of the frame next to the numbers, and the whole thing is one prompt away from being whatever fits your workflow.

Try these prompts

Copy any prompt below and paste it into FloopFloop to get started.

Build an aspect ratio calculator. Width and height number fields with a lock toggle: when locked, changing one dimension fills in the other to keep the same ratio (proportional resize). Show the simplified ratio (reduce with the GCD so 1920×1080 reads as 16:9), the decimal ratio, and the pixel size. Render a live preview frame in the current ratio using the CSS aspect-ratio property. Add preset chips (16:9, 4:3, 21:9, 1:1, 9:16, 3:2, 2:1, 5:4) that set the ratio and highlight when the current one matches. Keep it deterministic so the first render is hydration-safe, and remember the size in localStorage. 100% client-side.

Create an aspect ratio tool: type a width and height and get the ratio like 16:9, and let me lock the ratio so resizing one side updates the other. Keep it in the browser.

Build a tool for resizing images and video frames that keeps the aspect ratio — enter the original size and a new width, get the matching height. Add a dark theme and a live preview.

Build an aspect ratio calculator with common presets for video and social (16:9, 9:16, 1:1) and a visual preview of the frame.

Frequently asked questions

How does it work out the ratio?

It reduces the width and height by their greatest common divisor, so 1920×1080 and 1280×720 both come out as 16:9. It also shows the decimal ratio (16:9 ≈ 1.78) for when you need a single number.

What does locking the ratio do?

With the ratio locked, changing one dimension automatically fills in the other so the proportions stay identical — exactly what you want when resizing an image or video frame without stretching it. Unlock it to edit width and height freely.

Why does a 21:9 monitor show as 64:27?

Because 21:9 is a marketing label that isn't fully reduced. The true ratio of a 2560×1080 ultrawide is 64:27 — the calculator shows the exact reduced ratio while still offering 21:9 as a preset, so you get both the convention and the maths.

Can I resize to a specific width or height?

Yes — lock the ratio, then type the dimension you know (say a new width) and the calculator computes the matching height that preserves the shape. It works the same way in either direction.

Is anything uploaded?

No. Every calculation runs in your browser and your last size is saved to localStorage only. The single outbound surface is the /api/health probe.

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