What is a pixel size converter?

It calculates the missing dimension when you know one side and the aspect ratio. For example: if you want a 16:9 image at 1920px wide, it calculates the height as 1080px automatically.

How do I convert pixels to keep aspect ratio?

Enter your known width or height and the target aspect ratio (e.g., 16:9). The converter instantly shows the matching other dimension.

Can I convert between aspect ratios?

Yes. Enter your current pixel size and the target ratio (e.g., 1:1 for Instagram) and we show the new dimensions while discussing whether cropping or padding is needed.

What aspect ratios are supported?

All standard ratios: 1:1 (Instagram), 16:9 (YouTube), 4:3 (classic), 9:16 (Stories/TikTok), 3:2 (print), and custom ratios you enter.

Is this tool free to use?

Yes. There is no charge, no account, and no watermark on the output. Resizing happens entirely in your browser, so the image never leaves your device. You can keep the aspect ratio or set exact dimensions depending on your needs.

Pixel Size Converter — Pixel Size Converter

Pixel Size Converter

The aspect-ratio tool shows the matching width or height for any ratio — pick a ratio, enter one dimension, and the other fills in instantly. Do it all here in your browser — free, private, and with no uploads.

Why it matters: The aspect-ratio tool shows the matching width or height for any ratio — pick a ratio, enter one dimension, and the other fills in instantly.

How to resize images

1Upload your image. Everything stays in your browser — nothing is sent to a server.
2Pick a method — By Pixels for exact sizes, By % to scale proportionally, Aspect Ratio to reshape, or a Preset for social/print standards.
3Resize and download. Batch mode bundles every file into a single ZIP.

Best settings for this page: Open the tool, choose Aspect Ratio Calculator from the tabs, set your values, and download instantly.

All resizing runs locally in your browser. Your files are not uploaded to any server.

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