Make an image smaller for upload with Squoosh

A website can reject an image because its file is too large, even when it looks small on screen. This guide uses the free Squoosh browser tool; the Adobe Express comparison comes from Adobe's documentation.

The screenshots use Squoosh's built-in Large photo example. The example is a demonstration, not a recommended size for every upload.

1. Read the upload requirements

1. Check the destination's accepted file types, maximum file size and required pixel dimensions.
2. Keep your original image. Work on a copy.

Pixels describe width and height. KB and MB describe how much data the file contains. Changing one does not guarantee the other meets the requirement. If a form requires exact dimensions or a particular crop, follow those instructions first.

2. Open the image in Squoosh

1. Open Squoosh (opens in a new tab).
2. Click the large image button above Drop OR and choose your file. To follow this demonstration, select Large photo instead.
3. Leave the left Compress menu on Original Image. Use the right side for your changes.

Squoosh says image processing happens on your device. Its source documentation also says it collects visitor and before/after file-size analytics. Local image processing does not mean the website collects no data.

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Squoosh demonstration images, with the 2.8 MB red panda photo first

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Squoosh sample images. Choose the first, the red panda, to follow this example.

Open full-size image

3. Set the pixel dimensions if needed

1. On the right, turn on Resize.
2. Keep Maintain aspect ratio checked so the image keeps its proportions.
3. Enter the required Width. Squoosh calculates the height.

For this example, we changed 3872 × 2592 pixels to 1200 × 803. Leave Resize off if you must preserve the original dimensions. A 1200-pixel width is only our example; it is not a rule for photos, printing or official forms.

4. Compress and inspect the result

1. For a photo where JPG is accepted, choose MozJPEG in the right Compress menu.
2. Start at Quality 75. Wait for the file-size figure beside the right download arrow to update.
3. Drag the centre divider to compare details. Use the bottom + and − controls to change the preview zoom.
4. If the file is still too large, lower Quality a little and check again. If details become smeared or text becomes hard to read, increase it.

Our downloaded JPG was 117,572 bytes, shown as 118 kB, compared with the 2.79 MB original. It retained the chosen 1200 × 803 dimensions. Your result depends on the image and settings; compression can discard detail.

Use a format the destination accepts. A JPG cannot preserve a transparent background. For transparent artwork, consider PNG or WebP if the destination supports it.

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Squoosh showing a 1200 by 803 pixel JPEG at quality 75 and 118 kB

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Open full-size image

5. Download the changed copy

1. Click the right-hand download arrow. The left arrow downloads the original.
2. Open the saved file and inspect it at the size you will use.
3. Check its file size and dimensions, then upload that copy to the destination.

Aim a little below a strict limit rather than matching its rounded display exactly. If the upload still fails, recheck its file type and pixel requirements before reducing quality again.

If you are considering Adobe Express

For resizing one image, Adobe offers a free image-resizer quick action. Resizing an existing design page, including its text and other elements, is a separate Premium feature. Paying is worth considering when you need that design workflow; a smaller JPG alone does not require it.

If you need a square crop, Squoosh's proportional resize will not create it from a rectangular photo. Crop a copy in an image editor first, then compress it.

Sources: Squoosh source and privacy (opens in a new tab), Adobe's free image resizer (opens in a new tab), Adobe's design-page Resize help (opens in a new tab). No affiliate links.