How to Crop an Image to a Square, 4:3 or 16:9 Frame

What is the difference between cropping and resizing?

Cropping cuts the picture. The part you keep is saved at its original pixel detail, and everything outside the box is discarded. Resizing keeps the whole picture and changes its pixel dimensions.

That is why a crop from a large photo can still look sharp, while a tiny crop from a small photo will be small. If you crop a 300 × 300 area, the output is 300 × 300 pixels. Resize it afterwards if you need a specific size.

Which aspect ratio should I choose?

The ratio describes the shape of the box. The tool offers four choices. When you switch ratio, the box is redrawn at the largest size that fits within about 90 percent of the image and is centred, ready for you to move.

Platforms change their recommended sizes from time to time, so check the current help page of the site you are posting to. If it gives a pixel size rather than a ratio, the Aspect Ratio Calculator will tell you which shape it is.

How do I move and adjust the crop box precisely?

Drag inside the box to move it, and drag any of the eight handles on the corners and edges to change its size. With a fixed ratio, the box keeps its shape while you resize. Mouse and touch both work, so you can crop on a phone.

For fine control, focus the box and use the arrow keys. Each press moves it by 1 pixel, or by 10 pixels while holding Shift. The panel above the preview shows the crop size and its position from the top-left corner, measured in the original image’s pixels, not the shrunken preview.

How do I frame a better crop?

Leave some breathing room. Cropping tightly against a face or product edge tends to feel cramped, especially when a site later adds a rounded or circular mask. For profile pictures, centre the face and leave space above the head.

Look at where the subject faces. A person looking right usually sits better in the left part of the frame, with space in front of them. Horizons look calmer when they are not cut through the exact middle of a picture.

Check the edges for things you did not mean to keep, such as half a sign, a stray elbow or a sliver of another photo in a screenshot. Those are easier to spot when you look at the output preview rather than the full image.

Does cropping lower quality or file size?

Cropping keeps the original detail in the area you choose, but the result is saved as a new file. JPG and WebP outputs are encoded at quality 90, which keeps them visually clean. PNG output is lossless.

The file size usually drops because there are fewer pixels. The result panel shows the cropped dimensions and file size so you can check before downloading. JPG output cannot keep transparency, so transparent areas in a PNG are filled with white if you choose JPG.

Should I crop before or after other edits?

Crop first in most cases. Cropping removes the pixels you do not need, so any later resizing, compression or format conversion works on a smaller image and finishes faster. It also means the resized output is based on the framing you chose, rather than a smaller copy of the whole scene.

The main exception is when you are building several crops from one photo, such as a square avatar and a wide banner. Keep the original untouched and make each crop separately from it, rather than cropping a crop. Each pass is saved as a new file, so starting from the original keeps the best possible detail.

How do I crop for a specific platform?

Decide on the shape first, then the content. A wide 16:9 frame works for video thumbnails and slides, where text or a logo often sits alongside the subject. A square suits product grids and profile images, which many sites display small. A 4:3 frame is a comfortable middle ground for articles and documents.

Think about what the platform overlays. Profile pictures are often shown in a circle, so anything in the corners of a square crop may be hidden. Video thumbnails may have a duration label in a corner. Keep the important part of the image clear of those areas.

If you are unsure, preview the crop at the size it will be seen. A detail that is obvious at full size can disappear in a 100-pixel thumbnail, which is a good reason to crop tighter for small placements.

Can cropping hide private information?

Cropping does discard the pixels outside the box, so details that were cut away, such as a name in a screenshot margin, are not present in the downloaded file. The original on your device still has them, so share only the cropped copy. Camera metadata is not copied into the new file either, because the crop is redrawn from pixels. Check the preview carefully before sharing, since anything inside the box remains visible.

How to crop an image online

1. Choose the image. Select a JPG, PNG or WebP up to 25 MB, with each side no more than 8,192 pixels.
2. Pick a frame. Choose Free, 1:1, 4:3 or 16:9. The box appears centred on the picture.
3. Position the box. Drag to move, pull the handles to resize, and use the arrow keys for small adjustments. Watch the size and position readout.
4. Crop and download. Choose JPG, PNG or WebP, run the crop, check the preview, and download the file with “-cropped” in its name.

Example

Tips and limitations

FAQ

How do I crop a photo into a perfect square?

Select the 1:1 frame. The box stays square as you move and resize it.

Can I type exact crop coordinates?

No. Drag the box and use the arrow keys, then read the exact size and position shown above the preview.

How do I nudge the crop box by one pixel?

Focus the box and press an arrow key. Hold Shift to move 10 pixels at a time.

Why is my cropped image smaller than expected?

The output keeps the pixels inside the box, so a small box gives a small image. Use a larger source photo for larger crops.

Can I crop to a custom ratio such as 4:5?

There is no 4:5 preset. Use Free and size the box by eye, then adjust the exact size afterwards in the Image Resizer.

Will my PNG keep its transparent background?

Yes, if you save as PNG or WebP. JPG output fills transparent areas with white.

What does the position readout mean?

It shows how far the box’s top-left corner is from the image’s top-left corner, in original image pixels.

Can I undo a crop?

The original file is not changed. Move the box and crop again, or reset to start over.

Which file types can I crop?

JPG, PNG and WebP, up to 25 MB and 8,192 pixels on each side.

What is the downloaded file called?

Your original name with “-cropped” added, ending in the extension of the format you picked.

How do I crop for an Instagram portrait post?

Set a 4:5 ratio and frame the subject before exporting the cropped PNG or JPG.

Can I crop from the center automatically?

Choose a centered preset when available, or drag the box until the focus sits mid-frame.

Why did my crop export look softer?

Shrinking then upscaling softens edges—export at the crop’s native pixel size.

Should I crop before or after color correction?

Either works; many editors color-correct first so histograms use the final framing.

How do rule-of-thirds guides help?

Align eyes or horizons on the guide intersections for a steadier composition.

Can I crop animated GIFs frame by frame here?

This flow targets still images—use a GIF editor for multi-frame crops.

What if I need the same crop on many photos?

Note the ratio and approximate offsets, or batch-crop in a dedicated desktop tool.

Does cropping change DPI metadata?

Pixel dimensions change; DPI tags may stay or reset depending on the encoder.

How do I crop out a watermark cleanly?

Crop only if the watermark sits outside the keep region; otherwise content-aware edits are needed.

Can circular social avatars be cropped as squares first?

Yes—export a square, then the platform applies its circular mask.

Sources and further reading

• Canvas drawImage() (MDN)