Image Resizer & Compressor

How to Use the Image Resizer

1. Upload an image by dragging it onto the drop zone or clicking to browse your files. PNG, JPEG, WebP, GIF, and BMP are all supported.
2. Choose a size using the preset buttons (25%, 50%, 75%, 100%) or enter custom width and height values. Aspect ratio is locked by default to prevent distortion.
3. Select output format — keep the original format or convert to JPEG, PNG, or WebP.
4. Adjust quality using the slider for JPEG and WebP output. Lower values produce smaller files with more compression artifacts. 80-90% is usually ideal.
5. Download your resized image. The comparison panel shows original vs new file size and the savings percentage.

What This Tool Does

This image resizer and compressor processes your images entirely in your browser using the HTML5 Canvas API. When you upload an image, it is drawn onto an invisible canvas at your specified dimensions, then exported in your chosen format and quality level. The result is a resized, recompressed image file ready for download. Because all processing happens locally, your images are never uploaded to any server, making this tool ideal for sensitive or private images.

Image Compression Explained

Image compression comes in two types: lossy and lossless. JPEG and WebP use lossy compression, which discards some visual data to achieve smaller file sizes. At high quality settings (80-95%), the loss is usually imperceptible to the human eye, but file sizes can be reduced by 50-80%. PNG uses lossless compression, preserving every pixel exactly but producing larger files. WebP generally achieves 25-35% smaller files than JPEG at equivalent quality, making it the best choice for web use when browser support is not a concern.

When to Resize Images

Common reasons to resize images include optimizing for web performance (large images slow down page load times), meeting social media dimension requirements (Instagram 1080x1080, Twitter 1200x675, Facebook 1200x630), reducing file size for email attachments, and preparing images for specific print dimensions. For web use, images wider than 1920 pixels are rarely necessary, and compressing to WebP at 85% quality typically reduces file size by 70% or more without visible quality loss.

Supported Formats

• JPEG — Best for photographs and complex images. Lossy compression with adjustable quality. Widely supported everywhere.
• PNG — Best for graphics, logos, and images with transparency. Lossless compression, larger file sizes.
• WebP — Modern format with superior compression. Supports both lossy and lossless modes. 25-35% smaller than JPEG. Supported by all modern browsers.
• GIF / BMP — Supported as input formats. Output conversion to JPEG, PNG, or WebP is recommended for better compression.

Need to convert between image formats? Use the Image Format Converter. For generating placeholder images during development, try the Placeholder Image Generator. To create favicons from your images, use the Favicon Generator.