How to reduce the file size of a screenshot.

Why screenshots are so large

Most computers and phones save screenshots as PNG. PNG is lossless, so it keeps sharp text and lines but cannot throw detail away. A full screenshot of a 2,560 × 1,440 display holds about 3.7 million pixels, and a 4K screen at 3,840 × 2,160 holds about 8.3 million. Pages with photos, gradients or smooth shadows make PNG files bigger still, while flat pages with white backgrounds compress well.

So there are three levers: fewer pixels (crop and resize), a better-suited format, and compression toward a target size. The relationship between pixels and file size is explained in file size vs dimensions.

The right order of steps

1. Crop to the part that matters.
2. Resize if the width is more than the destination needs.
3. Convert or compress only after that.

This order works because every pixel you remove first is a pixel that never needs to be stored. Compressing a full screen and then cropping wastes quality.

Step 1: crop to what matters

Remove browser toolbars, taskbars, empty margins and anything private. Open Crop image, drag a selection over the useful part or enter Left, Top, Width and Height in pixels, export, and check the edges. A 1,920 × 1,080 screenshot cropped to a 960 × 540 area has one quarter of the pixels. Cropping also helps privacy, since notifications and tabs often appear at the edges. Your original stays unchanged.

Step 2: resize if it is very wide

Retina and 4K screenshots are often far wider than needed. For a chat message or a document, 1,200 to 1,600 pixels wide is usually plenty; for an email body, 600 to 800 pixels is common. Use Resize image to set a maximum width. It keeps proportions and does not stretch or enlarge. A 2,880 × 1,800 screenshot resized to a 1,440-pixel width becomes 1,440 × 900, a quarter of the pixel count.

Then look at the result at 100 percent zoom. Small text is the first thing to become unreadable. If it does, go back and choose a larger width, or crop tighter so the text is bigger relative to the image.

Step 3: pick the right format

Try Convert to JPG at a high quality setting or Convert to WebP and compare the sizes shown, rather than assuming either is smaller. Text-only screenshots often shrink well when resized but not much when switching format. The choice is explained in PNG vs JPG vs WebP.

Step 4: compress to a target size

When there is a hard limit, open Compress image, choose an output format, enter a maximum size in KB or MB and process. It shows the actual output size so you can see if it fits. WORDMIO uses decimal units, so 500 KB is 500,000 bytes. Set the target about 10 percent below the limit. If the result looks poor, reduce the pixel dimensions first and compress again, which retains more detail than squeezing the full-size picture. Note that PNG uses lossless encoding, so for hard targets JPG or WebP output gives the tool more room. For tiny limits see compressing to 100 KB and photo under 200 KB.

Worked example

You have a 3,024 × 1,964 PNG screenshot of about 3 MB and an email that bounces anything over 1 MB. The figures below are an illustration; actual sizes depend on content.

1. Crop out the browser bar and sidebar so you are left with, say, 2,400 × 1,500.
2. Resize to a maximum width of 1,400, giving 1,400 × 875. That is about one third of the pixels of the cropped version.
3. Check the file size. If it is under 1 MB, stop.
4. If not, compress to 900 KB in JPG or WebP and zoom in on text to confirm it is legible.

For other email limits see reducing image size for email.

Common mistakes

• Taking a screenshot of a screenshot. It reduces quality and does not reliably meet a size target.
• Renaming .png to .jpg. The file is unchanged.
• Compressing so hard that text becomes fuzzy.
• Leaving private information visible when you crop only for size.
• Compressing the same JPG again and again. Start from the original each time.

All these tools run in your browser, so your screenshots are not uploaded. Check the final file with Upload Check before you send it.

Frequently asked questions

Why are my screenshots so large?

Screenshots are usually saved as PNG, which is lossless, and high-resolution screens give millions of pixels. Cropping and resizing cut the pixel count and the file size.

How do I reduce a screenshot to under 1 MB?

Crop out unneeded areas, resize to about 1,200 to 1,600 pixels wide, then compress to a target slightly under 1 MB. Check that small text is still readable.

Is JPG or PNG better for screenshots?

PNG keeps text and lines crisp. JPG can be smaller for screenshots with photos, but low quality leaves fuzzy halos around text. Compare both.

Does resizing a screenshot reduce its quality?

It reduces detail, but a screenshot that is wider than its destination needs gains little from the extra pixels. Check readability at 100 percent zoom after resizing.