無料オンライン画像クロッパー
オンラインで素早く簡単に画像をトリミングします。
Frequently Asked Questions
What aspect ratios can I crop to?
You can crop to any aspect ratio freely, or lock to presets: 1:1 (square/Instagram), 16:9 (widescreen/YouTube), 4:3 (standard), 3:2 (DSLR/print), 2:3 (portrait), 9:16 (vertical/Stories). Enter custom dimensions in pixels for exact sizes.
Does cropping reduce image quality?
Cropping alone does not reduce quality — it simply removes pixels outside the selected area. If you resize the cropped area to larger dimensions than the crop, it will introduce blur. The tool crops without resampling for maximum quality.
What image formats does the cropper support?
Supported formats: JPG/JPEG, PNG, GIF, WebP, and BMP. Output is in the same format as your input. For transparent backgrounds, use PNG input to preserve transparency in the crop.
Is my image uploaded to a server when I use this tool?
No. The image is processed entirely in your browser using the HTML5 Canvas API. No image data is transmitted to any server — your photos stay private on your device.
Can I crop images to specific pixel dimensions for social media?
Yes. Common social media dimensions: Facebook cover 851×315, Instagram square 1080×1080, Twitter header 1500×500, LinkedIn cover 1584×396. Enter these exact pixel values in the crop dimension fields.
Is the 画像クロッパー free to use?
Yes, the 画像クロッパー on Allio Tools is completely free with no sign-up or registration required. It works directly in your browser.
How does the 画像クロッパー work?
オンラインで素早く簡単に画像をトリミングします。 No data is sent to a server — everything runs locally in your browser for maximum privacy and speed.
Do I need to install anything to use the 画像クロッパー?
No installation needed. The 画像クロッパー runs entirely in your web browser on any device — desktop, tablet, or mobile.
Is my data safe when using the 画像クロッパー?
Completely safe. The 画像クロッパー processes everything locally in your browser. No input data, results, or usage information is ever transmitted to or stored on any server.
Does the 画像クロッパー work offline?
After the page loads for the first time, the 画像クロッパー works without an internet connection for all client-side processing. Tools that fetch live external data (such as DNS or network lookups) require an active connection.
What image formats does the 画像クロッパー support?
The 画像クロッパー works with common image formats supported by your browser, including JPEG, PNG, WebP, and GIF. SVG support varies by tool. No format conversion plugin or driver is needed.
Does the 画像クロッパー work with large image files?
Yes. The 画像クロッパー processes files entirely in your browser using the Canvas API. Very large files (over 20 MB) may take a few extra seconds on older or lower-powered devices. Closing other tabs can free up memory for better performance.
Does the 画像クロッパー work on all browsers?
Yes. The 画像クロッパー is built with standard browser APIs and works on all modern browsers including Chrome, Firefox, Safari, and Edge — on both desktop and mobile. No plugins, extensions, or third-party software are required.
How do I save or export my results from the 画像クロッパー?
Select and copy the result text to paste into any document or app. For image tools, a Download button saves the file directly to your device. Your browser's built-in screenshot function also captures results quickly. No account or login is required.