什么是图片调整大小工具？
图片调整大小工具是一个免费的在线工具，Resize images with social media presets。
所有处理都在浏览器中进行，您的数据永远不会发送到服务器。
如何使用
- 在浏览器中打开工具
- 按照界面上的说明操作
- 获取结果并下载使用
- Preview the result and download your resized PNG.
主要特点
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.