Resize images

Resize an image: make photos smaller without making them look bad

A phone photo today has 12 to 48 megapixels and 3 to 10 MB – far too much for email, forms or your own website. Here is how to bring images down to a sensible size, how pixel dimensions differ from file size, and which values suit which purpose.

The short version

1. Drop your images into the Image Workshop – all at once is fine.
2. Under “Size”, pick a preset such as “Email & messenger (1600 px)”, or enter your own pixel value.
3. Under “Format & compression”, keep the quality between 75 and 85.
4. Download one by one or all together as a ZIP.

Pixels or MB: two kinds of “smaller”

“Resizing an image” can mean two things, and they are connected:

• Pixel dimensions (resolution): how many pixels wide and tall the photo is, e.g. 4032 × 3024. Fewer pixels make the image smaller on screen – and almost always make the file smaller too.
• File size in KB or MB: how much storage the file needs. It depends on the pixel dimensions, but also on the format (JPG, PNG, WebP) and the compression.

The pixel count almost always has the biggest effect. Halve width and height and only a quarter of the pixels remain – the file shrinks accordingly. The quality setting then saves a lot more. If the file has to fit under a fixed limit, see Compress an image to 200 KB.

Step by step

1. Load images. In the Image Workshop, click “Choose images” or drag the photos into the window. JPG, PNG, WebP, HEIC, AVIF, GIF and BMP are supported.
2. Set the size. Under “Size” → “Resize to”, choose what the images are fitted to: longest side, width, height, a width × height box, or percent. “Longest side” is usually best because portrait and landscape photos are treated the same.
3. Prevent enlarging. Leave “Don’t enlarge small images” on – otherwise small images would be scaled up and become blurry.
4. Check the quality. Click an image to open the before/after comparison slider. Old and new pixel dimensions and file sizes are shown below it.
5. Save. A single image downloads directly, several come as a ZIP. Under “File names” you can use patterns like holiday-{n}.

Which size for which purpose?

The Image Workshop has presets for the most common purposes. File sizes are guidelines for a typical phone photo saved as JPG at quality 82 – detailed subjects come out a little larger, skies and flat areas smaller.

For screens, a longest side of 1600 to 2000 pixels is almost always enough. Printing works differently: at 300 dpi you need 300 pixels per inch of print width, so a 4 × 6 inch print needs about 1800 × 1200 pixels. Photos meant for print are best resized only a little or not at all.

No visible loss of quality

Three things decide whether a resized photo still looks good:

• Clean downscaling. When a large photo is shrunk a lot in one step, fine patterns shimmer and edges turn jagged. The Image Workshop therefore shrinks large jumps in several halving steps, which keeps fine detail like hair or text much cleaner.
• The right quality. With JPG, WebP and AVIF the difference between quality 100 and 80 is hard to see, but the file is often only half as big. Below 60, blocky artifacts show up in flat areas.
• The right format. JPG for photos, PNG for screenshots, logos and graphics with text. WebP is 25 to 35% smaller than JPG at the same quality and ideal for websites.

Many images at once

The settings apply to every image on the workspace. You can load 200 holiday photos, choose “Longest side 1600 px” once and download them all as a ZIP. Portrait photos are handled just like landscape ones, because “Longest side” always follows the longer edge.

Everything runs in your browser. Photos are not uploaded, there is no limit on the number and no watermark. All metadata is removed when saving, including the GPS location – more in Remove GPS data from photos.

Alternatives: Windows, Mac, iPhone, command line

magick photo.jpg -resize "1600x1600>" -quality 82 photo-small.jpg
magick mogrify -path small -resize "1600x1600>" -quality 82 *.jpg

Frequently asked questions