# Crop Images — Crop images in bulk on Mac

Crop to an aspect ratio or an exact area, or trim plain borders automatically — one photo or a whole folder. Part of OneMacTools, 151 private tools in one native Mac app (macOS 26 or later); category: Images. Runs on your Mac; nothing is uploaded.

Crop photos to 1:1, 4:5, 3:4, 4:3, 3:2, 2:3, 16:9 or 9:16, keeping the centre, top or bottom. Or type an exact area — left, top, width and height in pixels or percent — and apply it to a whole batch. Or let it trim plain white or coloured borders around screenshots and scans automatically.

Page: https://www.onemactools.com/tools/crop-images · Download: https://www.onemactools.com/download · Pricing: https://www.onemactools.com/pricing

## How to use it
1. **Drop your images.** Add one image or a batch. The same crop is applied to each of them.
2. **Choose how to crop.** Aspect ratio for a standard shape, Exact area for a precise rectangle, or Trim borders to remove plain edges automatically.
3. **Set the details.** Pick the ratio and which part to keep, type the area, or set the tolerance for trimming.
4. **Click Crop.** Each image is cropped and saved with “cropped” added to its name, in its original format.
5. **Check the results.** The cropped copies are saved in a new dated folder in Downloads › OneMacTools. Use the Preview (eye) button or Show in Finder. Your originals are not changed.

## Options
- **Crop by:** Aspect ratio crops to a standard shape. Exact area cuts out a rectangle you specify. Trim borders removes plain margins around the picture automatically.
- **Left, top, width, height:** Shown for Exact area: four numbers, measured from the top-left corner, such as 100, 50, 800, 600. An area that runs past the edge is clipped to the image.
- **Measured in:** Shown for Exact area: Pixels, or Percent of the image. Percent is best for a batch of different-sized images, because the same numbers fit each one.
- **Aspect ratio:** Shown for Aspect ratio: 1:1 Square, 4:5 Portrait, 3:4, 4:3, 3:2, 2:3, 16:9 or 9:16. The largest area of that shape is kept.
- **Keep:** Shown for Aspect ratio: Centre, Top or Bottom. This decides which part is kept when the height is trimmed. Width is always trimmed evenly from both sides.
- **Tolerance:** Shown for Trim borders: 0 to 60, 10 by default. The border colour is taken from the top-left corner. Raise the tolerance for scans and photos where the margin isn't perfectly even; lower it if part of the picture is being trimmed.
- **Dragging the box:** With Crop by set to Exact area, the photo appears in the window with a crop box. Drag it, or pull a corner to resize; the Left, top, width, height numbers update as you go, and typing numbers moves the box. It snaps to the centre and edges, and the arrow keys nudge it (hold Shift for bigger steps).

## Tips
- Use Keep: Top for portraits and headshots when cropping to a wider shape, so heads aren't cut off.
- Trim borders works best on screenshots, scans and product photos on a plain background. Make sure the top-left corner is part of the border.
- To crop the same region from a batch of screenshots, such as one panel of an app, use Exact area in pixels.
- For social media sizes with smart cropping around faces, use Social Media Image Resizer instead.

## Questions
**How do I crop many photos at once on a Mac?**
Drop them all onto Crop Images, choose an aspect ratio, exact area or Trim borders, and click Crop. Every photo gets the same crop.

**How do I make a photo square?**
Choose Aspect ratio and 1:1 Square. The largest square that fits is kept, centred on the photo, or towards the top or bottom if you change Keep.

**How do I remove white space around a scan or screenshot?**
Choose Trim borders. It finds the edge of the content by comparing every pixel with the corner colour. Raise the tolerance if a faint edge or shadow is left behind.

**What aspect ratio should I use for Instagram?**
4:5 Portrait takes up the most space in the feed, 1:1 Square is the classic post, and 9:16 suits stories and Reels.

**Can I crop the same area out of different-sized images?**
Yes. Use Exact area measured in Percent of the image, such as 10, 10, 80, 80 to keep the middle 80% of each.

**Why does Trim borders say the image is a single colour?**
Nothing in the image differs from the corner colour by more than the tolerance. Lower the tolerance and try again.

**Can I drag the crop area instead of typing numbers?**
Yes. Choose Exact area and drag the box on the photo in the window. The numbers in the panel follow the box, and the same area is used for every photo in the batch, measured in pixels or percent as you choose.