How to Resize Images on Mac Without Quality Loss

Learn how to resize images on macOS without compromising quality using the built-in Preview app and Automator for batch processing.

1. Open your image in Preview. Locate your image file in Finder. Right-click the file, select Open With, and choose Preview.app.
2. Open the Adjust Size tool. In the top menu bar, navigate to Tools and select Adjust Size. Alternatively, click the Markup toolbar icon if visible and select the Resize icon.
3. Input dimensions and resampling settings. Ensure 'Scale proportionally' is checked to prevent distortion. Verify 'Resample image' is active and choose 'Lanczos' from the dropdown menu to maintain sharpness during scaling.
4. Save the resized image. Click OK to apply the changes. Navigate to File and select Save to overwrite, or File > Export to create a new file with different settings.
5. Batch resize multiple images. Select all files in Finder, right-click, select Quick Actions, then choose Convert Image. Select your format and choose 'Actual Size' or a custom resolution to resize multiple assets simultaneously.