Image Resizer

Image resizing sets the pixel dimensions of the output independently of the source file’s original size. The resizer scales the pixel grid up or down to the width and height you specify, drawing the result to a canvas element and encoding it in your chosen output format. No file is uploaded at any point.

The tool accepts JPG, PNG, WebP, GIF, BMP, and SVG files up to 20 MB and outputs in WebP, JPG, or PNG.

Resizing vs Cropping vs Compressing

These three operations are frequently confused because they all reduce image file size, but they produce different results on the pixel content.

Resizing scales the entire image to new dimensions. Every pixel from the original is resampled to fit the target width and height. The full composition of the image is preserved at a smaller or larger scale. A 4000×3000 photograph resized to 800×600 contains the entire scene at one fifth the linear resolution.

Cropping removes regions of the image entirely. A 4000×3000 photograph cropped to 800×600 retains only the selected 800×600 pixel region of the original frame — the rest is discarded. The remaining content is not scaled.

Compressing re-encodes the image at lower quality without changing pixel dimensions. A 4000×3000 JPEG compressed from quality 95 to quality 75 stays at 4000×3000 pixels but reduces file size by removing imperceptible detail.

Common Resizing Use Cases

Email attachments have size limits ranging from 5 MB to 25 MB depending on the provider. A DSLR photograph at original resolution often exceeds these limits. Resizing to 1920×1080 or 1200×900 and re-encoding as WebP or JPEG typically reduces a 12 MB RAW-derived JPEG to under 500 KB while preserving screen-quality detail.

Social media platforms impose maximum pixel dimensions on uploaded images and apply their own compression on ingest. Resizing to the platform’s specified dimensions before uploading prevents automatic downsampling, which often produces worse results than a controlled resize at high quality.

Website performance depends on serving images at the dimensions they will be displayed. A 4000-pixel wide image displayed at 400 pixels in a browser grid forces the browser to download 100 times more pixel data than necessary. Resizing to the display dimensions before uploading to the CMS eliminates this waste.

Output Format Selection

WebP is the default output format. It produces the smallest file size of the three options for photographic content and is supported by 97 percent of active browsers. Choose JPG when the destination platform requires it or when email compatibility across older clients matters. Choose PNG when lossless output is needed — for graphics, logos, screenshots, and images with flat colour where compression artefacts are visible.

The quality slider controls compression for WebP and JPG outputs. PNG output is always lossless and the quality slider is hidden when PNG is selected.

Aspect Ratio Lock

Enabling the lock ratio checkbox calculates the opposite dimension automatically when you change width or height. This prevents distortion of the image geometry. Unlocking the ratio allows you to stretch or squeeze the output to non-proportional dimensions — useful for profile images and avatars with fixed square or circular crop requirements.