Image Resizer

Resize images by exact pixel dimensions or percentage with optional aspect-ratio lock.

Drag & drop an image here

or click to browse

What is this tool? Image Resizer?

Resizing images is one of the most-asked-for image operations on the web, for profile pictures with a strict pixel limit, blog images that need to fit a layout, social media thumbnails, or shrinking photos before email. Our resizer lets you specify exact pixel dimensions, percentage scaling, and choose any common output format. It runs entirely in your browser using the Canvas API, so your photos never leave your device.

How do you use this tool? Image Resizer

  1. Upload your image, Drag any PNG, JPG, WebP or GIF into the drop zone, or click to browse.
  2. Set your dimensions, Type a target width or height, or use percent. Keep "Aspect ratio" on to scale proportionally.
  3. Pick output format and quality, WebP for the smallest size, PNG for transparency, JPG for max compatibility.
  4. Download, Click Download to save the resized image.

Common Use Cases

Prepare web and app assets

Resize photographs, thumbnails, avatars, and banners to the exact dimensions required by a component.

Reduce upload size

Lower pixel dimensions before submitting images to forms, email, or storage services.

Create responsive variants

Generate several widths for srcset, art-direction, or content-management breakpoints.

Match print or marketplace specifications

Produce images with required pixel dimensions while preserving the intended aspect ratio.

Why is this tool useful?

Exact pixel control

Enter the required width and height rather than estimating with a visual drag operation.

Aspect-ratio protection

Lock proportions to prevent accidental stretching when changing one dimension.

Immediate dimension preview

Review the result before downloading and catch an incorrect orientation or target size.

Best Practices

  • ✓ Keep the aspect ratio locked unless distortion is intentional. Crop when you need a different shape instead of stretching the image.
  • ✓ Resize from the highest-resolution original, not from an already reduced copy.
  • ✓ Avoid enlarging small images significantly, because interpolation cannot recreate missing detail.
  • ✓ Choose dimensions based on the actual display slot and device density, not an arbitrary percentage.
  • ✓ After resizing, inspect text, thin lines, and faces for softness or ringing.

Practical examples

Resize a 4:3 photo by width
Input
Source: 4000×3000, target width: 1200 px, aspect ratio locked.
Output
1200×900. The height is calculated automatically to preserve the original 4:3 ratio.
Reduce an image to 50%
Input
Source: 1920×1080, scale: 50%.
Output
960×540. Reducing dimensions usually looks cleaner than enlarging a small source.

Frequently Asked Questions

Scaling down (e.g. 4000 × 3000 → 800 × 600) is essentially lossless. Scaling up adds blur, there's no detail to invent. Always start from the largest source you have.

Common targets: Instagram square 1080 × 1080, Twitter post 1200 × 675, Open Graph 1200 × 630, favicon 192 × 192.

No. Everything runs in your browser; we never see your file.

No. The tool creates a new result in the browser. Your original remains unchanged unless you overwrite it after downloading.

The tool does not add ownership restrictions to your output. You remain responsible for rights to the source material and for complying with third party licenses.

Related Guides

Images

How to Resize Images Without Losing Quality

The difference between upscaling and downscaling, why aspect ratio matters, and how to resize images for web without visible quality loss.

6 min read

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