What Is an Aspect Ratio?
An aspect ratio describes the proportional relationship between an image's width and height, written as W:H - for example 16:9 for widescreen video or 1:1 for a square Instagram post. Two images can look completely different in size but still share the same aspect ratio.
How This Tool Checks Your Aspect Ratio
The moment you upload an image, the tool reads its exact pixel dimensions and reduces the width-to-height relationship to its simplest whole-number ratio (like 16:9 or 4:3), so you instantly know what you're working with before deciding how to crop it.
How to Crop to a Specific Ratio
- Upload: Drop an image or browse for one.
- Pick a ratio: Choose a preset like 1:1, 16:9, or 9:16 - or leave it on Free for a custom shape.
- Position the crop: Drag the selection box to move it, or drag a corner handle to resize it. When a preset ratio is active, the box always keeps that exact shape.
- Export: Click Export cropped image to download the result as a PNG at full resolution.
Common Aspect Ratios and Where They're Used
- 1:1 - Instagram posts, profile pictures, album covers.
- 4:3 - Classic photography and older TV/monitor screens.
- 3:2 - Standard DSLR and mirrorless camera photos.
- 16:9 - YouTube thumbnails, widescreen video, most modern monitors.
- 9:16 - Instagram Reels, TikTok, YouTube Shorts, phone wallpapers.
- 21:9 - Ultrawide monitors and cinematic banners.
Privacy & Security
Your image never leaves your device. Everything - reading the dimensions, drawing the crop selection, and exporting the final file - happens locally in your browser using the Canvas API. Nothing is uploaded to a server, no account is required, and there are no usage limits.
Frequently Asked Questions
Does cropping reduce image quality?
No. The export keeps the original pixel resolution of the selected region - you're only removing the parts outside the selection, not resampling what remains.
Can I crop to a ratio that isn't in the preset list?
Yes - use Free mode and drag the handles to any shape you need. The exact ratio and pixel size update live as you resize.
What file format does the export use?
The cropped image downloads as a PNG, which preserves transparency if your original image had any.