Free Online Image Resizer
How to Use This Image Resizer
- Upload your imageDrag it onto the drop zone or click to browse your files. The tool supports JPG, PNG, WebP, and GIF formats. After uploading, you'll see a preview along with the original dimensions and file size.
- Resize by dimensionsBy Dimensions lets you enter exact pixel values for width and height. The aspect ratio lock (enabled by default) ensures your image doesn't stretch - change one dimension and the other adjusts automatically. Unlock it if you intentionally want different proportions.
- Resize by percentageBy Percentage scales your image relative to its original size. Use the slider or type a value - 50% halves the dimensions, 200% doubles them. Quick-select buttons make common scales one click away.
- Pick a preset sizePreset Sizes offers ready-made dimensions for social media platforms and common resolutions. Click any preset to instantly set the target dimensions - perfect for preparing images for Instagram, Facebook, Twitter, or LinkedIn.
- Choose format and crop, then downloadSelect an output format if you want to convert the image (JPEG, PNG, or WebP). Enable "Crop to fit" if you want the image to fill the exact dimensions without letterboxing. Click "Resize" to process, then download your resized image.
All resizing happens locally in your browser. Your images never leave your device.
What is Image Resizing?
Image resizing changes the pixel dimensions of an image — its width and height in pixels. A 4000×3000 pixel photo resized to 2000×1500 contains one-quarter as many pixels, producing a proportionally smaller file. Resizing is distinct from compression: a dedicated image resizer changes dimensions, while a compressor reduces file size at the same dimensions.
Why aspect ratio matters
Maintaining aspect ratio is crucial when resizing. The aspect ratio is the proportional relationship between width and height — common ratios include 16:9 (widescreen), 4:3 (traditional), and 1:1 (square). Changing dimensions without preserving this ratio stretches or squishes the image, distorting its contents.
Social media dimension requirements
Social media platforms have specific image dimension requirements. Instagram posts display best at 1080×1080 pixels, stories need 1080×1920, Facebook covers use 820×312, and LinkedIn banners require 1584×396. Using incorrect dimensions results in cropping, letterboxing, or poor display quality.
Upscaling vs. downscaling
When making images larger (upscaling), quality inevitably decreases because the software must invent pixels that don't exist. Downscaling generally looks good because information is combined rather than fabricated. For web use, images rarely need to exceed 1920 pixels wide, as most screens cap out at that resolution.
Fit vs. crop-to-fit
The choice between fitting and cropping matters when target dimensions don't match the original aspect ratio. Fitting preserves the entire image but may add empty space. Cropping fills the entire target area but cuts off edges. Center cropping works well for most subjects but may clip important details in some compositions.
Image Resizer Features
- Three resize modesBy pixel dimensions, by percentage, or by preset size.
- Aspect-ratio lockPrevents stretching when you only set one dimension.
- Social media presetsInstagram, Facebook, Twitter/X, LinkedIn, YouTube, Pinterest.
- Crop-to-fitFill exact dimensions with center-cropping, no letterboxing.
- Format conversionOutput JPG, PNG, or WebP regardless of the input format.
- Supports JPG, PNG, WebP, and GIFCovers every common web image format.
- Live previewSee the resized output with original-vs-new dimensions before downloading.
- Runs in your browserImages never upload. Fast, private, and free forever.
When to Resize Images
- Blog & website imagesResize large photos to 1600–2000 px wide for fast, retina-friendly loads.
- Social media postsUse the right aspect ratio so nothing gets cropped by the platform.
- E-commerce product photosMatch Shopify, WooCommerce, Amazon, and eBay recommended sizes.
- Profile pictures and avatarsCrop square photos for GitHub, LinkedIn, Slack, and Discord.
- Email marketingKeep images under 1 MB and under 600 px wide for reliable delivery.
- Online applications and formsVisa, passport, and school portals often require exact pixel dimensions.
- Thumbnails and previewsGenerate compact versions for galleries, carousels, and lazy loading.
- Upscaling low-res imagesIncrease dimensions modestly (up to 150%) for small prints.
Social Media Image Size Cheat Sheet