Resize Image Online

Resize any image to exact pixel dimensions, percentage, or ecommerce presets. Instant, free, no quality loss.

Runs in your browser — images never leave your device
Drop your image here or click to upload
JPG, PNG, WebP, GIF, BMP · No size limit
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Ecommerce Presets
Percentage Resize
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How It Works

1

Upload Your Image

Drop any image — JPG, PNG, WebP, GIF, or BMP. No size limit, no sign-up.

2

Set New Dimensions

Enter exact pixel sizes, pick an ecommerce preset, or choose a percentage to scale by.

3

Download

Click Apply, preview the result, and download your resized image as PNG or JPG.

How to Resize an Image

Resizing an image changes its pixel dimensions — making it larger or smaller — while optionally preserving the original aspect ratio to prevent distortion.

Image resizing is one of the most common tasks in digital image editing. Whether you need to prepare product photos for an online store, fit images into social media dimensions, reduce file size for faster web loading, or meet specific print requirements, resizing is the fundamental operation that makes it all possible. Modern browsers can perform high-quality image resizing entirely client-side using the Canvas API, meaning your images never need to leave your device.

There are two primary approaches to resizing: absolute (pixel-based) and relative (percentage-based). Absolute resizing lets you specify exact width and height in pixels — for example, 1000x1000 for Amazon product listings. Relative resizing scales the image by a percentage of its original dimensions — for example, 50% to halve the size. Both approaches can preserve the aspect ratio (the proportional relationship between width and height) to prevent the image from appearing stretched or squished.

Aspect Ratio

The aspect ratio is the proportional relationship between an image's width and height. A 1920x1080 image has a 16:9 aspect ratio. When resizing with the aspect ratio locked, changing the width automatically adjusts the height proportionally (and vice versa), ensuring the image doesn't appear distorted. Unlocking the aspect ratio allows you to stretch or compress the image to any arbitrary dimensions — useful when you need to fit a specific frame like Facebook's 1200x630 cover photo format.

Downscaling vs. Upscaling

Downscaling (making an image smaller) is straightforward and generally produces good results because you're discarding pixels. The browser's resampling algorithm blends adjacent pixels together smoothly. Upscaling (making an image larger) is more challenging because the algorithm must invent new pixel data that doesn't exist in the original. Small upscales (up to 150-200%) usually look acceptable, but extreme upscaling will introduce blur or artifacts. For high-quality upscaling beyond 200%, consider AI-powered upscaling tools that use neural networks to intelligently reconstruct detail.

Ecommerce Image Requirements

Major ecommerce platforms have specific image dimension requirements for optimal display. Amazon recommends at least 1000x1000 pixels for zoom functionality. Shopify supports images up to 4472x4472 but recommends 2048x2048 for sharp display on retina screens. eBay recommends at least 1600 pixels on the longest side. Meeting these requirements ensures your product images look professional and support all platform features like zoom and gallery views.

Image Resize Use Cases

Ecommerce Product Photos

Online marketplaces like Amazon, Shopify, eBay, and Etsy each have specific image dimension requirements. Resizing ensures your product photos meet platform standards for optimal display, zoom functionality, and fast loading — directly impacting conversion rates and search ranking.

Social Media Content

Each social platform has ideal image dimensions: Instagram posts (1080x1080), Facebook covers (1200x630), Pinterest pins (1000x1500), Twitter/X posts (1600x900). Correctly sized images prevent cropping, display sharply on all devices, and look professional in feeds.

Email Attachments & Newsletters

Large images slow down email delivery and may be blocked by email servers. Resizing images to reasonable dimensions (600-800px wide for newsletters) reduces file size dramatically, ensuring fast delivery and reliable display across all email clients.

Print & Physical Media

Print projects require specific dimensions based on physical size and DPI. A 4x6 inch print at 300 DPI needs a 1200x1800 pixel image. Resizing to the exact required dimensions ensures your prints come out sharp without unexpected cropping or stretching.

Website Optimization

Oversized images are the number one cause of slow-loading websites. A 4000px wide photo displayed at 800px wastes bandwidth and hurts page speed scores. Resizing to the actual display size can reduce file size by 80-90%, dramatically improving load times and SEO ranking.

Thumbnail Generation

Creating thumbnails for galleries, video previews, blog posts, and file managers requires consistent sizing. Batch-resizing images to standard thumbnail dimensions (150x150, 300x300) ensures visual consistency and optimal loading performance across your entire site or application.

Image Resize Tool Features

Exact Pixel Dimensions

Enter precise width and height in pixels for perfect sizing every time.

Aspect Ratio Lock

Keep proportions intact automatically. Toggle off for free-form resizing.

Ecommerce Presets

One-click presets for Amazon, Shopify, eBay, Instagram, and Facebook.

Percentage Scaling

Scale by 25%, 50%, 75%, 150%, or 200% of original dimensions.

100% Private

Everything runs in your browser. Images never leave your device.

Unlimited & Free

No limits, no sign-up, no watermarks. Resize as many images as you need.

Frequently Asked Questions

Is my image uploaded to a server?
No. All resizing happens in your browser using the HTML5 Canvas API. Your image never leaves your device — completely private and secure.
Does resizing reduce image quality?
Downscaling (making smaller) has minimal quality impact — the browser smoothly blends pixels. Upscaling (making larger) may introduce some softness since new pixel data must be interpolated. For best results when upscaling significantly, consider AI-powered upscaling tools. Downloading as PNG preserves maximum quality; JPG applies standard compression.
What does "lock aspect ratio" mean?
When the aspect ratio is locked (the padlock icon is closed), changing the width automatically calculates the correct height to maintain the image's proportions, and vice versa. This prevents stretching or squishing. Unlock it when you need to resize to specific non-proportional dimensions like Facebook's 1200x630.
What are the best image sizes for Amazon?
Amazon requires a minimum of 1000 pixels on the longest side for zoom functionality, and recommends 2000 pixels or more. The ideal size is 2000x2000 pixels for square product images. Use the Amazon (1000x1000) preset as a minimum, or manually enter 2000x2000 for optimal quality.
What size should my Shopify product images be?
Shopify supports images up to 4472x4472 pixels and recommends 2048x2048 for sharp display on retina screens. All product images should use the same dimensions for consistent gallery appearance. Use the Shopify (2048x2048) preset for optimal results.
How do I resize an image without stretching it?
Keep the aspect ratio locked (padlock icon closed). When you change either width or height, the other dimension will automatically adjust to maintain the original proportions. This ensures the image is never distorted.
Can I resize a transparent PNG?
Yes. PNG images with transparency are fully supported. The alpha channel is preserved through resizing. Download as PNG to keep transparency — JPG format does not support transparency and will fill transparent areas with white.
Is there a maximum image size?
There is no enforced limit. The tool handles any image size your browser can process. Very large images (10,000+ pixels) may take a moment to process depending on your device. Most browsers support canvases up to 16,384 pixels on each side.
What image formats are supported?
The tool supports JPG, PNG, WebP, GIF, BMP, and any image format your browser can display. Output is available as PNG (lossless, supports transparency) or JPG (compressed, smaller file size).
Does it work on mobile?
Yes, fully responsive. Works on iPhone, Android, iPad, and any device with a modern browser. The interface adapts to smaller screens with touch-friendly controls.
Can I make an image larger?
Yes. You can upscale images by entering larger dimensions or using the 150% or 200% presets. Browser-based upscaling works well for moderate increases (up to 2x). For larger upscales that need to remain sharp, consider using an AI-powered upscaler that can intelligently reconstruct detail.
How many images can I resize?
Unlimited. Since everything runs client-side with no server, there are no daily limits or usage caps. Resize as many images as you need, completely free.
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