Image Resizer
A premium, privacy-first image resizing tool that works entirely in your browser. Resize single or multiple images using width & height, percentage, longest edge, shortest edge, fit inside box, or fill canvas methods. Choose from smart presets for Instagram, Facebook, YouTube, Twitter, and more. Preview changes side-by-side before downloading. Batch process hundreds of images and download as individual files or a ZIP archive. All processing happens locally using the Canvas API — your images never leave your device.
Your Files Never Leave Your Device
All image resizing happens entirely in your browser using the Canvas API. Your images are never uploaded to any server.
Upload Images
Drag & drop images, click to browse, or paste from clipboard
Six resize methods, and when each one is actually the right pick
Width & Height isn't always what you want — Fit Inside Box and Fill Canvas solve different problems.
"Resize this image" usually means one of several different things depending on the goal: an exact pixel size for a platform's upload spec, a percentage scale-down to shrink a file, or fitting a photo into a fixed-size box without distorting it. This tool exposes six distinct resize methods precisely because "just make it smaller" isn't specific enough to get a good result every time.
How to use it
- Upload an image (JPG, PNG, WEBP, AVIF, BMP, GIF, TIFF, or ICO).
- Pick a resize method: Width & Height for exact dimensions, Percentage to scale proportionally, Longest Edge or Shortest Edge to constrain one dimension while the other follows automatically, Fit Inside Box to shrink a photo to fit within bounds without cropping, or Fill Canvas to fill an exact box by cropping the overflow.
- If you're targeting a specific platform, use the aspect-ratio lock so the image scales proportionally instead of distorting — then crop separately first if the target ratio doesn't match your original photo.
- Enable Sharpen After Resize when enlarging an image, since upscaling invents new pixels from neighboring ones and can come out soft without it.
- Optionally convert the output format (to JPG, PNG, WEBP, or AVIF) alongside the resize, and download the result.
Common use cases
- Matching a platform's exact upload spec — Instagram (1080×1080 square, 1080×1350 portrait), Facebook link previews (1200×630), YouTube thumbnails (1280×720), or a LinkedIn banner — using Width & Height for the precise pixel target.
- Shrinking a batch of photos for web performance — using Percentage or Longest Edge to cut file size without manually calculating dimensions for every image.
- Fitting a photo into a fixed content-card size without stretching or cropping it — Fit Inside Box shrinks to fit, leaving any extra space rather than distorting the image.
- Cropping a photo to fill a banner or hero image exactly — Fill Canvas resizes and crops together so the result fills the target box edge-to-edge.
Resize Methods
Choose from multiple ways to resize your images
Width && Height
Set exact pixel dimensions
Percentage
Scale by a percentage
Longest Edge
Set the longest side
Shortest Edge
Set the shortest side
Fit Inside Box
Fit within bounds
Fill Canvas
Fill with cropping
Frequently Asked Questions
Everything you need to know about resizing images
How does browser-based image resizing work?
What image formats are supported?
What resize methods are available?
Will resizing reduce image quality?
What are the social media presets?
Can I resize multiple images at once?
What does the 'Fit Inside Box' method do?
How does 'Fill Canvas' differ from 'Fit Inside Box'?
Can I change the DPI of my images?
Is my privacy protected?
How Image Resizing Works
A complete guide to resizing images effectively
Understanding Image Dimensions
Image dimensions are measured in pixels (width × height). Resizing changes these dimensions, affecting the image's physical size and file size. Reducing dimensions creates smaller files, while increasing dimensions (upscaling) can introduce blurriness. Always resize to the exact dimensions needed for your use case.
Aspect Ratio Explained
Aspect ratio is the proportional relationship between width and height (e.g., 16:9, 4:3, 1:1). Maintaining the aspect ratio when resizing prevents distortion. When you see black bars or cropping, it's because the target dimensions don't match the original aspect ratio.
When to Use Each Resize Method
Width & Height is best when you need exact pixel dimensions. Percentage is ideal for quick scaling. Longest/Shortest Edge is perfect for ensuring images meet specific size limits. Fit Inside Box is great for thumbnails. Fill Canvas works best for banners and covers where complete coverage matters.
Resizing for Social Media vs Print
Social media images are optimized for screen display at 72 DPI with smaller file sizes. Print images require higher resolution (at least 150-300 DPI) and larger dimensions. Always size up for print — the DPI setting tells the printer how densely to place pixels on paper.
Tool Overview
A closer look at Image Resizer — how it works, who it's for, and where it fits in your workflow.
Images come in every shape and size from your camera, phone, or design tool, but the platform you're publishing to expects something specific — Instagram's 1080×1080 square, a 1200×630 Open Graph card, a 1920-wide hero image, or a thumbnail gallery. The Image Resizer handles six resizing modes so you can fit your image to exactly the dimensions you need: absolute width/height, percentage scaling, longest edge, shortest edge, fit inside a box, or fill a canvas.
Smart presets cover the most common social media and device dimensions: Instagram post, story, and profile; Facebook cover and share; YouTube thumbnail; Twitter/X card; LinkedIn banner; and device wallpapers. The side-by-side preview lets you compare the resized image to the original before committing, and batch processing applies the same resize to hundreds of images at once. Additional options let you sharpen after resize, adjust DPI for print, and convert the output format in the same operation.
Resizing is a pixel-level operation that your browser handles natively via the Canvas API. No image data is uploaded to any server, no file is stored externally, and you can resize as many images as you like with no rate limits or account required.
Key Features
Everything you get with this tool, at a glance.
6 Resize Modes
Width/height, percentage, longest edge, shortest edge, fit inside, fill canvas.
Social Media Presets
One-click dimensions for Instagram, Facebook, YouTube, Twitter, and LinkedIn.
Side-by-Side Preview
Compare the original and resized image before downloading.
Batch Processing
Apply the same resize to hundreds of images at once.
Sharpen, DPI & Format
Sharpen after resize, set print DPI, and convert output format simultaneously.
Canvas API, Fully Local
Resizing uses the browser's Canvas API — no uploads, no limits.
How to Use Image Resizer
Get from zero to done in four quick steps — no account, no learning curve.
Upload your image
Select one or more images. You can resize a single image or batch hundreds.
Choose resize method
Pick from width/height, percentage, longest edge, shortest edge, fit inside, or fill canvas.
Apply smart presets
Use one-click social media presets or enter custom dimensions.
Preview and download
Compare the result with the original, then download individually or as a ZIP.
Practical Examples
Real input and output pairs so you know exactly what to expect.
Instagram square post
Input
Original: 4000×3000 photo · Preset: Instagram Post
Output
Resized: 1080×1080 — ready to upload
OG image card
Input
Original: 1920×1080 · Preset: Open Graph
Output
Resized: 1200×630 — perfect for social sharing
Batch thumbnail resize
Input
50 product photos · 50% of original
Output
50 resized images in ZIP — 75% smaller each
Guides & Articles
Learn how to get the most out of this tool with our in-depth guides.
Social Media Image Sizes: A Practical Resizing Guide
The exact pixel dimensions for Instagram, Facebook, X, LinkedIn, and YouTube — plus how to resize images without the platform cropping them for you.
Resize and Compress Images for Email, Forms, and Online Uploads
That 12 MB camera photo will bounce off half the forms you try to upload it to. Here's how to right-size images without visibly losing quality.
Part of Image Editing
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