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Image Resizer

Resize any image to exact dimensions or percentage. Social media presets included. 100% browser-based. Zero uploads.

No Upload Required Custom Dimensions Social Media Presets JPG / PNG / WebP

Drop your image here

or click to browse files from your device

Supports JPG, PNG, WebP, GIF, BMP —Max 20 MB

How it works

Three simple steps —everything happens in your browser.

1

Upload your image

Drag and drop or click to select an image from your device. JPG, PNG, WebP, GIF, and BMP are all supported.

2

Set your dimensions

Enter custom width & height, use a percentage slider, or pick a social media preset. Lock the aspect ratio to prevent distortion.

3

Download

Preview the result side-by-side with the original, then download in JPG, PNG, or WebP format.

Why choose ToolKnit for resizing images?

100% Private —No Server Uploads

Your image never leaves your device. All resizing is done locally using the HTML5 Canvas API. No data is sent to any server —ever.

Instant Results

Since everything runs on your machine, there's no upload delay. Images are resized in milliseconds, regardless of file size.

Social Media Presets

One-click presets for Instagram, Twitter/X, LinkedIn, Facebook, YouTube, and Pinterest. No more Googling "what size is an Instagram post?"

Flexible Output

Choose between JPG, PNG, and WebP output formats. Control quality for lossy formats to balance file size and visual clarity.

Pro Tips

  • ●Keep aspect ratio locked to prevent your image from looking stretched or squished.
  • ●Use JPG at 80-85% quality for photos —it gives the best balance of size and quality.
  • ●Use PNG for screenshots, logos, or images with text —lossless compression keeps edges sharp.
  • ●Avoid upscaling beyond 2x —the image will look blurry since new pixels must be interpolated.
FAQ

Frequently Asked Questions

Does resizing reduce image quality?

Downscaling generally preserves quality well. Upscaling can introduce blurriness since the browser must interpolate new pixels. For best results when enlarging, keep the scale under 2x.

What image formats are supported?

JPG, PNG, WebP, GIF, BMP, and TIFF — any format your browser can display. You can also choose the output format independently.

Is my image uploaded to a server?

No. All processing happens locally in your browser using the Canvas API. Your image never leaves your device.

Can I resize multiple images at once?

Currently this tool handles one image at a time for maximum control. For batch compression, check out our Compress Image tool.