画像リサイズツールとは？
画像リサイズツールは、Resize images with social media presetsの無料オンラインツールです。
すべての処理はブラウザで実行され、データがサーバーに送信されることはありません。
使用方法
- ブラウザでツールを開く
- 画面の指示に従って操作する
- 結果を取得してダウンロードする
- Preview the result and download your resized PNG.
主な特徴
The built-in presets cover the most commonly recommended dimensions: Instagram square posts (1080x1080), Instagram stories and Reels (1080x1920), YouTube thumbnails (1280x720), Facebook profile and cover sizes, Twitter/X header images, and Pinterest pins. Selecting a preset automatically fills in the exact width and height for you.
Understanding Aspect Ratio
Aspect ratio is the relationship between an image's width and height. Changing only one dimension breaks the ratio and distorts the image. With Maintain aspect ratio enabled, the resizer scales both dimensions proportionally, and the Aspect Ratio Calculator is available if you need to work out dimensions for a specific ratio like 16:9 or 4:3.
Tips
- Resize before compressing for the smallest final file size.
- Use 100% zoom in the preview to check sharpness after resizing.
- For print, target at least 300 DPI at the final print size.
- Downscaling improves perceived sharpness — it's a great way to clean up large camera photos.