Image Resizer & Converter

Resize, compress, and convert images — all in your browser, no upload.

Drop an image or click to upload

PNG, JPG, WebP, GIF

Image Resizer — What It Does

Resize images to exact pixel dimensions, compress them to reduce file size, and convert between JPEG, PNG, and WebP formats — all without uploading anything to a server. The tool uses the browser's built-in Canvas API for fast, private, client-side processing. Drag and drop an image or click to select, adjust dimensions and quality, then download the result.

When to Use Each Format

  • JPEG — Best for photographs. Lossy compression gives small file sizes. Does not support transparency.
  • PNG — Lossless compression. Supports transparency (alpha channel). Best for logos, icons, and screenshots with sharp edges.
  • WebP — Modern format with superior compression for both photos and graphics. Supports transparency. Preferred for web delivery in 2024+.

Common Image Size Targets

  • Web hero image — 1920×1080px, JPEG/WebP at 80% quality
  • Blog post thumbnail — 800×450px or 1200×630px for Open Graph
  • Avatar / profile picture — 400×400px, square crop
  • Email inline image — Keep under 600px wide, JPEG at 75% quality
  • App icon — 1024×1024px PNG source, then resize for each target platform

Tips for Best Results

  • Always start from the original — Resizing an already-compressed image compounds quality loss. Keep the original and re-export from it.
  • Use WebP for websites — WebP images are 25–34% smaller than equivalent JPEG at the same visual quality, improving page load speed.
  • Don't upscale small images — Enlarging an image beyond its native resolution adds pixels artificially and results in blurry output. Resize down, not up.

Frequently Asked Questions

Does the image get uploaded to a server when I resize it?
No. All processing happens entirely in your browser using the HTML5 Canvas API. Your image data never leaves your device, making this tool completely private and suitable for sensitive or confidential images.
What output formats are supported?
You can export the resized image as JPEG, PNG, or WebP. JPEG is best for photographs and offers small file sizes with a quality slider. PNG is lossless and ideal for graphics with transparency. WebP provides the best compression for both photos and graphics and is supported by all modern browsers.
How does the quality slider affect file size?
The quality slider controls lossy compression level for JPEG and WebP outputs (PNG is always lossless). Setting quality to 80% typically reduces file size by 50–70% compared to 100% with minimal visible difference. Values below 60% show noticeable artefacts. 80–85% is the recommended range for web images.
What does maintaining aspect ratio mean?
When "maintain aspect ratio" is enabled, changing either the width or height automatically updates the other dimension proportionally, so the image is not stretched or squashed. For example, a 1200×800 image scaled to width 600 will automatically set height to 400.
What is the maximum image size this tool can handle?
Since processing happens in the browser, limits depend on your device memory and browser. Most modern browsers handle images up to 30–50 megapixels without issues. Very large images (100MP+) may cause slowdowns or run out of GPU memory on the Canvas element.