Image Resizer

Uploading a 4000-pixel-wide photo when your layout only needs 800 pixels wastes bandwidth and hurts SEO. ConvertFlow's image resizer lets you set exact dimensions with aspect-ratio lock and live preview — processed instantly in your browser.

Convert Now — Free

No account · No upload · Files stay on your device

How to convert image resizer with ConvertFlow

  1. Upload your image.
  2. Enter target width and height (lock aspect ratio if needed).
  3. Preview and download the resized image.

Key features

  • Precise pixel dimensions
  • Maintain aspect ratio toggle
  • Live preview
  • Local processing
  • Supports all major image formats

Common use cases

  • Blog and website image preparation
  • Social media size requirements
  • Thumbnail generation
  • Email-friendly image dimensions

Why browser-based conversion?

Traditional online converters upload your files to remote servers. That adds wait time and raises privacy concerns — especially for personal photos, contracts, and business documents. ConvertFlow uses modern browser APIs to process files locally. Your data never leaves your device, and conversions complete in seconds without queueing behind other users.

Read more about this approach in our browser-based conversion guide.

Frequently asked questions

Downscaling usually looks great. Upscaling beyond original dimensions may look soft.

Match your layout's maximum display width. For retina screens, multiply by 1.5–2x.

Use the Image Resizer first, then the Image Compressor for maximum file size reduction.