Image Resizer (SNS & E-Commerce)
Easy and fast one-shot conversion to recommended sizes for various SNS and EC sites.
Supports batch processing, trimming, and adding margins of multiple images.
Drag & drop images
or click to select
Multiple OK (max 20, 30MB each) / JPEG, PNG, GIF, WebP
Processing...
About
This is a free tool that converts the size (resolution) of an image to match the desired size. The biggest feature is that the ``recommended sizes'' for various SNS and EC sites such as Instagram, X, Amazon, and Rakuten are preset.
You can also choose the "fit method" when matching the size. If you do not want to crop the photo, you can select "Fit (add margins)", and if you want to display it to fill the screen, you can select "Cover (crop)".
You can drag and drop multiple images (up to 20 images) at the same time to process them all at once and download them as a ZIP file. All processing is completed on your device using the browser's Canvas API, so there is no need to worry about your uploaded photos being saved on an external server.
How to Use
Choose purpose and size
Select the desired size from the SNS or EC tab. At this time, you can also set the "fitting method" such as whether to include margins or not.
Drop image
Drag and drop the image you want to convert. You can also choose the output format (JPEG/PNG, etc.).
Download results
The process is completed in an instant. Check the preview and choose whether to save all files as a ZIP file or individually.
Glossary
- Resize
- The process of changing an image's pixel dimensions (resolution). Downsizing reduces file size while upsizing may introduce blurriness.
- Aspect Ratio
- The proportional relationship between an image's width and height. Common ratios include 16:9 (widescreen), 4:3, 1:1 (square), and 9:16 (stories).
- Cropping
- Removing unwanted portions of an image to keep only the desired area. Used for improving composition or fitting specific dimensions.
- DPI / PPI
- Dots/Pixels Per Inch — the density of dots or pixels in one inch. Print typically requires 300+ DPI while web images use 72 DPI.
- EXIF Data
- Metadata embedded in photos including date, camera model, GPS coordinates, etc. Resizing through Canvas API automatically strips this data for privacy.
- Canvas API
- An HTML5 API for manipulating image pixel data in the browser. This tool uses Canvas API for all resize and crop operations.
- WebP Format
- An image format by Google offering ~25-35% smaller file sizes than JPEG at equivalent quality. Ideal for faster web page loading.
FAQ
- Q.Are images uploaded to a server?
- No. All processing is done locally in your browser using Canvas API. Your images are never sent to any external server.
- Q.Can I resize multiple images at once?
- Yes. Select multiple files or drag and drop them for batch resizing.
- Q.How do I resize for Instagram (square)?
- Select the "Instagram Post (1080×1080px)" preset. Images with different aspect ratios will be automatically cropped or have padding added.
- Q.Will resizing reduce image quality?
- Downscaling shows virtually no visible quality loss. Upscaling uses pixel interpolation which may slightly blur fine details compared to the original.
- Q.What image formats are supported?
- Input: JPEG, PNG, WebP, GIF (still). Output options include JPEG, PNG, and WebP with adjustable quality settings.
- Q.Is EXIF data (location info) removed?
- Yes. Processing through Canvas API automatically strips all EXIF metadata including GPS coordinates and capture dates.
Use Cases
Image optimization for SNS
When you want to post a vertical photo taken with a smartphone with margins without cropping it to horizontal format (1200 x 675) for X (old Twitter).
Product registration on EC site
Significantly reduces the work involved in batch converting multiple product photos with different sizes and aspect ratios to square (white background), which is required by Amazon and Rakuten.