📐 Image Resizer
Resize images by pixels, percentage, or social media presets — your files never leave your browser
Drag & drop an image here
or click to browse — JPG, PNG, WebP
How Image Resizing Works
Resizing changes the number of pixels in an image. When you make an image smaller (downscaling), multiple pixels are combined into fewer pixels. When you make it larger (upscaling), the computer must invent new pixels based on the existing ones.
Interpolation Methods
When resizing, the browser uses interpolation to determine the color of new pixels. The Canvas API uses bilinear interpolation by default:
- Nearest-neighbor: Fastest, but creates jagged edges (pixelation). Good for pixel art.
- Bilinear: Smooth, good for photos. Default for most browsers.
- Bicubic: Even smoother, better for upscaling. Used by Photoshop's "Bicubic" option.
The Canvas API's drawImage() method uses the browser's built-in interpolation, which is typically bilinear — excellent for most use cases.
Downscaling vs Upscaling
- Downscaling (e.g., 4000px → 1000px): Generally produces excellent results. Detail is lost, but the image appears sharp and clean. A 75% size reduction typically looks nearly identical to the original.
- Upscaling (e.g., 500px → 2000px): Always produces some blur or pixelation since you're asking the computer to create detail that doesn't exist. For best results with upscaling, consider AI upscaling tools.
Social Media Image Requirements
Each social media platform has specific image size recommendations. Using incorrect sizes leads to unwanted cropping, blurry covers, or slow loading:
- Twitter/X Header: 1500 × 500 px — The narrow aspect ratio (3:1) means most photos need significant cropping.
- Facebook Cover: 1200 × 630 px — Displays at 820 × 312 on desktop but 640 × 360 on mobile. Keep important content centered.
- LinkedIn Banner: 1200 × 627 px — Similar to Facebook. Text-safe area is the center 800px.
- YouTube Channel Art: 2560 × 1440 px — This is the full TV size; the "safe area" for all devices is just 1546 × 423 px in the center.
Step-by-Step Guide
- Upload an image — Drag and drop or click to select a JPG, PNG, or WebP file.
- Choose a resize method: Enter exact dimensions, pick a percentage, or select a social media preset.
- Lock aspect ratio (optional) — Click the 🔗 button to maintain proportions when changing width or height.
- Preview the result — See original and resized versions side by side.
- Download — Save the resized image to your device.
Frequently Asked Questions
Downscaling (making smaller) generally preserves quality well — the browser uses interpolation to smooth pixels. Upscaling (making larger) will make the image appear blurry or pixelated since you can't create detail that wasn't in the original.
Resizing scales the entire image proportionally (or to specified dimensions), keeping all content. Cropping removes parts of the image to change the aspect ratio or focus on a specific area. This tool resizes; it doesn't crop.
Common social media cover sizes: Twitter/X header 1500×500, Facebook cover 1200×630, LinkedIn banner 1200×627, YouTube channel art 2560×1440. Using the exact recommended size avoids unwanted cropping by the platform.
This tool processes one image at a time to give you precise control over dimensions and preview. For batch resizing of multiple images with the same settings, you can process them one after another with your preferred settings.