How to crop an image with only standard Mac features

ナイフ Knife
Updated : Dec 27, 2021

I will show you how to crop an image using only standard Mac functions.

Here, I will introduce two methods, “Preview.app” and “Photos.app” of the genuine Mac apps, but I will also explain the advantages and disadvantages.

List of methods for cropping images and advantages / disadvantages

MethodAdvantagesDisadvantages
① “Preview.app”・Cropping can be square,
circular, or any shape
・Nothing special
② “Photos.app”・Can be completed
within the “Photos.app”
・Cropping can be only square
Mr. Otter
Mr. Otter

How should we use the two methods properly?

Little devil fox
Little devil fox

If you manage your images with the “Photos.app”, ② is recommended.

<meta charset="utf-8">Little devil fox
Little devil fox

In addition, you can open the image from the “Photos” app with the “Previewa.pp”, so if the function is insufficient in ②, you can also use the method ①.

<meta charset="utf-8">Mr. Otter
Mr. Otter

It looks convenient!

Then, use ① for one image file, and use ② or ① for the images managed by the “Photos.app” as needed.

① “Preview.app”

①-1 Show “Markup Toolbar”

▶ In “Preview.app”, open the image you want to crop.

Mac "Preview.app"
Click to enlarge

▶ Show the “Markup Toolbar”.

You can show it in one of the following three ways.

  • a) From the toolbar, click the “Markup” icon
  • b) From the menu bar, click “View” -> “Show Markup Toolbar”
  • c) On the keyboard shortcut, press shift + command ⌘ + A keys

a) Toolbar

Mac "Preview.app"
Click to enlarge

Below is an enlarged view around the arrow

Mac "Preview.app"
Click to enlarge

b) Menu bar

Mac "Preview.app"
Click to enlarge

Below is an enlarged view around the arrow

Mac "Preview.app"
Click to enlarge

c) Keyboard

Mac US Keyboard
Click to enlarge

▶ When the “Markup Toolbar” appears, click the “Selection Tools” icon on the far left of the toolbar.

Mac "Preview.app"
Click to enlarge

Below is an enlarged view around the arrow

Mac "Preview.app"
Click to enlarge

▶ When the “Selection Tools” items appear, click one of the following four.

ItemDescription
Rectangular SelectionSelect a range
with a rectangle (or a square)
Elliptical SelectionSelect a range
with an ellipse (or a circle)
Lasso SelectionSelect a range freehand
Smart LassoSelect some people or objects
from the image
Mac "Preview.app"
Click to enlarge
<meta charset="utf-8">Mr. Otter
Mr. Otter

I don’t understand the meaning of “Smart Lasso“!

How is this different from the usual “Lasso Selection”?

<meta charset="utf-8">Little devil fox
Little devil fox

I will explain with a concrete example after this, so if you look at it, you will be able to grasp the image.

<meta charset="utf-8">Little devil fox
Little devil fox

First of all, I will explain the basic function “Rectangular / Elliptical / Lasso Selection”.

“Smart Lasso” will be explained later.

①-2 How to use “Rectangular / Elliptical / Lasso Selection”

▶ Drag the mouse or trackpad to select a range.

In addition, in the case of “Rectangular Selection” or “Elliptical Selection”, the following keyboard operations are possible.

How to selectOperation
Select by square or circleHold down
the shift key,
and drag
Select around the drag start positionHold down
the option ⌥ key,
and drag
Select by square or circle
around the drag start position
Hold down
the shift + option ⌥ keys,
and drag

▶ A dashed line is displayed on the border of the selected range.

Mac "Preview.app"
Click to enlarge

▶ With the range selected, you can crop the image by performing one of the following operations.

  • a) From the toolbar, click the “Crop the Selection” icon
  • b) From the menu bar, click “Tools” -> “Crop”
  • c) On the keyboard shortcut, press command ⌘ + K keys

a) Toolbar

Mac "Preview.app"
Click to enlarge

Below is an enlarged view around the arrow

Mac "Preview.app"
Click to enlarge

b) Menu bar

Mac "Preview.app"
Click to enlarge

Below is an enlarged view around the arrow

Mac "Preview.app"
Click to enlarge

c) Keyboard

Mac US Keyboard
Click to enlarge

The figure below is the result of cropping.

Mac "Preview.app"
Click to enlarge

Also, the following operation removes the inside of the selection and leaves the surroundings, contrary to the above result.

  • On the keyboard, press delete ⌫ key

Mac US Keyboard
Click to enlarge

The figure below is the result of cropping.

Mac "Preview.app"
Click to enlarge

①-3 How to use “Smart Lasso”

<meta charset="utf-8">Mr. Otter
Mr. Otter

When is “Smart Lasso” used?

<meta charset="utf-8">Little devil fox
Little devil fox

It is convenient to use when you want to crop some people or objects from an image.

<meta charset="utf-8">Mr. Otter
Mr. Otter

Then, what is the difference between “Lasso Selection” and “Smart Lasso”?

<meta charset="utf-8">Little devil fox
Little devil fox

With “smart lasso”, if you specify the cropping border, you can automatically select the right range.

<meta charset="utf-8">Mr. Otter
Mr. Otter

I can’t still see.

What exactly happens when we use “Smart Lasso”?

<meta charset="utf-8">Little devil fox
Little devil fox

Below, I compared the results of specifying the cropping range when using “Lasso Selection” on the left and “Smart Lasso” on the right.

【Lasso Selection】

Mac プレビュー.app
Click to enlarge

【Smart Lasso】

Mac プレビュー.app
Click to enlarge
<meta charset="utf-8">Mr. Otter
Mr. Otter

Oh, it’s totally different!

When selecting with “Lasso Selection”, my hand trembles and I can’t specify it well.

In addition, the area around the cropping is left behind, and the parts that I don’t want to cut are also cut.

<meta charset="utf-8">Mr. Otter
Mr. Otter

With “Smart Lasso”, there is a little bit left around the cropping, but in some cases this is enough!

<meta charset="utf-8">Little devil fox
Little devil fox

It seems that the difference is well understood, so I will explain how to use it from here.

▶ Click the “Selection Tools” icon on the far left of the toolbar.

Mac プレビュー.app
Click to enlarge

Below is an enlarged view around the arrow

Mac プレビュー.app
Click to enlarge

▶ When the “Selection Tools” items appear, click “Smart Lasso”.

Mac "Preview.app"
Click to enlarge

Drag the mouse or trackpad to select a range.

The mouse cursor (mouse pointer) becomes a thick red line, so specify that the line should be traced over the cropping border.

Please refer to the video below for the actual specification.

▶ With the range selected, you can crop the image by performing one of the following operations.

  • a) From the toolbar, click the “Crop the Selection” icon
  • b) From the menu bar, click “Tools” -> “Crop”
  • c) On the keyboard shortcut, press command ⌘ + K keys

The figure below is the result of cropping.

Mac プレビュー.app
クリックで拡大表示

▶ Also, the following operation removes the inside of the selection and leaves the surroundings, contrary to the above result.

  • On the keyboard, press delete ⌫ key

The figure below is the result of cropping.

Mac プレビュー.app
クリックで拡大表示

② “Photos.app”

②-1 Create a duplicate (backup)

Not limited to cropping, it is recommended to create a duplicate (backup) in advance by the following method when editing with the “Photos.app”.

▶ Make the “Photos.app” a list of images.

mac "Photos.app"
Click to enlarge

▶ Right-click the image you want to duplicate (backup) and select “Duplicate 1 photo” from the menu that appears.

mac "Photos.app"
Click to enlarge

Below is an enlarged view around the arrow

mac "Photos.app"
Click to enlarge

▶ As shown in the figure, when the same image is created, duplication (backup) is complete.

The image used for cropping after this can be either of the two images.

mac "Photos.app"
Click to enlarge

②-2 Show “Edit Tools”

▶ From the list of images in the “Photos.app”, click the image you want to crop, then press the return key on your keyboard.

mac "Photos.app"
Click to enlarge

Click the image to select it, then press return

Mac US Keyboard
Click to enlarge

▶ When the image editing screen appears, click the tab “Crop” at the top of the screen.

mac "Photos.app"
Click to enlarge

Below is an enlarged view around the arrow

mac "Photos.app"
Click to enlarge

▶In ①, select an appropriate item from “Aspect” on the right side of the screen.

In ②, drag the white marks displayed at the four corners of the image to specify the cropping range.

mac "Photos.app"
Click to enlarge

You can undo and redo while editing, so please try again if necessary.

【Undo】

Mac US Keyboard
Click to enlarge

【Redo】

Mac US Keyboard
Click to enlarge

▶ When cropping is complete, click the yellow “Done” button at the top right of the screen to confirm (save).

mac "Photos.app"
Click to enlarge

Below is an enlarged view around the arrow

mac "Photos.app"
Click to enlarge

▶ This is the end of the explanation of the cropping method in the “Photos.app”.

But if you want to extract the image as one file, you can save it to the desktop etc. by dragging and dropping.

The following video was taken of that situation.

Reference information

About Cropping in the “Preview.app” on Apple’s official website

Extract an image or remove a background in Preview on Mac
In Preview on your Mac, extract an image to work with it separately, or use the Instant Alpha tool t...
Spa cat
Spa cat

This is the end of this article.

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